# Mozilla Thunderbird (en-US) 78.10.0

Mozilla Thunderbird (en-US) 78.10.0, released April 15, 2021, fixes 46 CVEs in Mozilla Thunderbird (en-US). None of them is reported as exploited. Patch Radar priority: Urgent. The latest Mozilla Thunderbird (en-US) is 159.0, which also fixes every one of these CVEs.

- Web page: https://patchblox.com/security/fix/windows-app/mozilla.thunderbird-78.10.0
- Platform: Windows apps
- Released: Apr 15, 2021
- Priority: Urgent (Closes CVE-2021-23978, rated Critical)
- CVEs: 46, exploited: 0, on CISA KEV: 0
- Superseded by: [Mozilla Thunderbird (en-US) 159.0](https://patchblox.com/security/data/product/windows-app/mozilla-thunderbird-en-us.md), the latest version, which also fixes every CVE listed here

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [Mozilla Thunderbird (en-US)](https://patchblox.com/security/data/product/windows-app/mozilla-thunderbird-en-us.md) |  | 78.10.0 |

## CVEs this fix closes

| CVE | Priority | Title | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2021-23978](https://patchblox.com/security/data/cve/CVE-2021-23978.md) | Urgent | Firefox ESR and 2 others: Mozilla developers reported memory safety bugs present in Firefox 85 and Firefox ESR 78.7. | 8.8 | 0.0153 |  |
| [CVE-2021-23968](https://patchblox.com/security/data/cve/CVE-2021-23968.md) | Urgent | Firefox ESR and 2 others: If Content Security Policy blocked frame navigation, the full destination of a redirect served in the… | 4.3 | 0.0131 |  |
| [CVE-2021-23969](https://patchblox.com/security/data/cve/CVE-2021-23969.md) | Urgent | Firefox ESR and 2 others: As specified in the W3C Content Security Policy draft, when creating a violation report, "User agents… | 4.3 | 0.0121 |  |
| [CVE-2020-26950](https://patchblox.com/security/data/cve/CVE-2020-26950.md) | High | Firefox ESR and 2 others: In certain circumstances, the MCallGetProperty opcode can be emitted with unmet assumptions resulting… | 8.8 | 0.4233 |  |
| [CVE-2020-26971](https://patchblox.com/security/data/cve/CVE-2020-26971.md) | High | Firefox ESR and 2 others: Certain blit values provided by the user were not properly constrained leading to a heap buffer overflow… | 8.8 | 0.0190 |  |
| [CVE-2021-23994](https://patchblox.com/security/data/cve/CVE-2021-23994.md) | High | Firefox ESR and 2 others: A WebGL framebuffer was not initialized early enough, resulting in memory corruption and an out of bound… | 8.8 | 0.0176 |  |
| [CVE-2020-26973](https://patchblox.com/security/data/cve/CVE-2020-26973.md) | High | Firefox ESR and 2 others: Certain input to the CSS Sanitizer confused it, resulting in incorrect components being removed. | 8.8 | 0.0162 |  |
| [CVE-2020-35113](https://patchblox.com/security/data/cve/CVE-2020-35113.md) | High | Firefox ESR and 2 others: Mozilla developers reported memory safety bugs present in Firefox 83 and Firefox ESR 78.5. | 8.8 | 0.0157 |  |
| [CVE-2020-26960](https://patchblox.com/security/data/cve/CVE-2020-26960.md) | High | Firefox ESR and 2 others: If the Compact() method was called on an nsTArray, the array could have been reallocated without updating… | 8.8 | 0.0156 |  |
| [CVE-2020-26974](https://patchblox.com/security/data/cve/CVE-2020-26974.md) | High | Firefox ESR and 2 others: When flex-basis was used on a table wrapper, a StyleGenericFlexBasis object could have been incorrectly… | 8.8 | 0.0153 |  |
| [CVE-2020-26968](https://patchblox.com/security/data/cve/CVE-2020-26968.md) | High | Firefox ESR and 2 others: Mozilla developers reported memory safety bugs present in Firefox 82 and Firefox ESR 78.4. | 8.8 | 0.0151 |  |
| [CVE-2021-23987](https://patchblox.com/security/data/cve/CVE-2021-23987.md) | High | Firefox ESR and 2 others: Mozilla developers and community members reported memory safety bugs present in Firefox 86 and Firefox… | 8.8 | 0.0142 |  |
| [CVE-2021-23999](https://patchblox.com/security/data/cve/CVE-2021-23999.md) | High | Firefox ESR and 2 others: If a Blob URL was loaded through some unusual user interaction, it could have been loaded by the System… | 8.8 | 0.0137 |  |
| [CVE-2021-23964](https://patchblox.com/security/data/cve/CVE-2021-23964.md) | High | Firefox ESR and 2 others: Mozilla developers reported memory safety bugs present in Firefox 84 and Firefox ESR 78.6. | 8.8 | 0.0136 |  |
| [CVE-2021-29946](https://patchblox.com/security/data/cve/CVE-2021-29946.md) | High | Firefox ESR and 2 others: Ports that were written as an integer overflow above the bounds of a 16-bit integer could have bypassed… | 8.8 | 0.0130 |  |
| [CVE-2020-26959](https://patchblox.com/security/data/cve/CVE-2020-26959.md) | High | Firefox ESR and 2 others: During browser shutdown, reference decrementing could have occured on a previously freed object, resulting… | 8.8 | 0.0130 |  |
| [CVE-2021-23960](https://patchblox.com/security/data/cve/CVE-2021-23960.md) | High | Firefox ESR and 2 others: Performing garbage collection on re-declared JavaScript variables resulted in a user-after-poison, and… | 8.8 | 0.0129 |  |
| [CVE-2020-35112](https://patchblox.com/security/data/cve/CVE-2020-35112.md) | High | Firefox ESR and 2 others: If a user downloaded a file lacking an extension on Windows, and then "Open"-ed it from the downloads… | 8.8 | 0.0127 |  |
| [CVE-2020-26970](https://patchblox.com/security/data/cve/CVE-2020-26970.md) | High | Thunderbird: When reading SMTP server status codes, Thunderbird writes an integer value to a position on the stack… | 8.8 | 0.0125 |  |
| [CVE-2021-23954](https://patchblox.com/security/data/cve/CVE-2021-23954.md) | High | Firefox ESR and 2 others: Using the new logical assignment operators in a JavaScript switch statement could have caused a type… | 8.8 | 0.0119 |  |
| [CVE-2021-23995](https://patchblox.com/security/data/cve/CVE-2021-23995.md) | High | Firefox ESR and 2 others: When Responsive Design Mode was enabled, it used references to objects that were previously freed. | 8.8 | 0.0118 |  |
| [CVE-2021-23981](https://patchblox.com/security/data/cve/CVE-2021-23981.md) | High | Firefox ESR and 2 others: A texture upload of a Pixel Buffer Object could have confused the WebGL code to skip binding the buffer… | 8.1 | 0.0115 |  |
| [CVE-2021-24002](https://patchblox.com/security/data/cve/CVE-2021-24002.md) | High | Firefox ESR and 2 others: When a user clicked on an FTP URL containing encoded newline characters (%0A and %0D), the newlines would… | 8.8 | 0.0113 |  |
| [CVE-2021-4127](https://patchblox.com/security/data/cve/CVE-2021-4127.md) | High | Thunderbird: An out of date graphics library (Angle) likely contained vulnerabilities that could potentially be exploited. | 9.8 | 0.0095 |  |
| [CVE-2020-15685](https://patchblox.com/security/data/cve/CVE-2020-15685.md) | High | Thunderbird: Improper Neutralization of Special Elements used in a Command ('Command Injection') | 8.8 | 0.0088 |  |
| [CVE-2021-29950](https://patchblox.com/security/data/cve/CVE-2021-29950.md) | High | Thunderbird: Thunderbird unprotects a secret OpenPGP key prior to using it for a decryption, signing or key import… | 7.5 | 0.0085 |  |
| [CVE-2021-29949](https://patchblox.com/security/data/cve/CVE-2021-29949.md) | High | Thunderbird: When loading the shared library that provides the OTR protocol implementation, Thunderbird will initially… | 7.8 | 0.0032 |  |
| [CVE-2020-35111](https://patchblox.com/security/data/cve/CVE-2020-35111.md) | Routine | Firefox ESR and 2 others: When an extension with the proxy permission registered to receive <all_urls>, the proxy.onRequest callback… | 4.3 | 0.0143 |  |
| [CVE-2021-23973](https://patchblox.com/security/data/cve/CVE-2021-23973.md) | Routine | Firefox ESR and 2 others: When trying to load a cross-origin resource in an audio/video context a decoding error may have resulted,… | 6.5 | 0.0137 |  |
| [CVE-2020-26958](https://patchblox.com/security/data/cve/CVE-2020-26958.md) | Routine | Firefox ESR and 2 others: Firefox did not block execution of scripts with incorrect MIME types when the response was intercepted… | 6.1 | 0.0136 |  |
| [CVE-2020-26966](https://patchblox.com/security/data/cve/CVE-2020-26966.md) | Routine | Firefox ESR and 2 others: Searching for a single word from the address bar caused an mDNS request to be sent on the local network… | 6.5 | 0.0135 |  |
| [CVE-2020-26978](https://patchblox.com/security/data/cve/CVE-2020-26978.md) | Routine | Firefox ESR and 2 others: Using techniques that built on the slipstream research, a malicious webpage could have exposed both an… | 6.1 | 0.0133 |  |
| [CVE-2020-26953](https://patchblox.com/security/data/cve/CVE-2020-26953.md) | Routine | Firefox ESR and 2 others: It was possible to cause the browser to enter fullscreen mode without displaying the security UI; thus… | 4.3 | 0.0129 |  |
| [CVE-2020-26965](https://patchblox.com/security/data/cve/CVE-2020-26965.md) | Routine | Firefox ESR and 2 others: Some websites have a feature "Show Password" where clicking a button will change a password field into… | 6.5 | 0.0126 |  |
| [CVE-2020-26956](https://patchblox.com/security/data/cve/CVE-2020-26956.md) | Routine | Firefox ESR and 2 others: In some cases, removing HTML elements during sanitization would keep existing SVG event handlers and… | 6.1 | 0.0123 |  |
| [CVE-2021-29945](https://patchblox.com/security/data/cve/CVE-2021-29945.md) | Routine | Firefox ESR and 2 others: The WebAssembly JIT could miscalculate the size of a return type, which could lead to a null read and… | 6.5 | 0.0120 |  |
| [CVE-2020-26961](https://patchblox.com/security/data/cve/CVE-2020-26961.md) | Routine | Firefox ESR and 2 others: When DNS over HTTPS is in use, it intentionally filters RFC1918 and related IP ranges from the responses… | 6.5 | 0.0117 |  |
| [CVE-2021-23984](https://patchblox.com/security/data/cve/CVE-2021-23984.md) | Routine | Firefox ESR and 2 others: A malicious extension could have opened a popup window lacking an address bar. | 6.5 | 0.0111 |  |
| [CVE-2021-23953](https://patchblox.com/security/data/cve/CVE-2021-23953.md) | Routine | Firefox ESR and 2 others: If a user clicked into a specifically crafted PDF, the PDF reader could be confused into leaking cross-origin… | 4.3 | 0.0106 |  |
| [CVE-2020-26951](https://patchblox.com/security/data/cve/CVE-2020-26951.md) | Routine | Firefox ESR and 2 others: A parsing and event loading mismatch in Firefox's SVG code could have allowed load events to fire, even… | 6.1 | 0.0105 |  |
| [CVE-2021-23991](https://patchblox.com/security/data/cve/CVE-2021-23991.md) | Routine | Thunderbird: If a Thunderbird user has previously imported Alice's OpenPGP key, and Alice has extended the validity… | 6.8 | 0.0104 |  |
| [CVE-2021-23982](https://patchblox.com/security/data/cve/CVE-2021-23982.md) | Routine | Firefox ESR and 2 others: Using techniques that built on the slipstream research, a malicious webpage could have scanned both an… | 6.5 | 0.0074 |  |
| [CVE-2021-23998](https://patchblox.com/security/data/cve/CVE-2021-23998.md) | Routine | Firefox ESR and 2 others: Through complicated navigations with new windows, an HTTP page could have inherited a secure lock icon… | 6.5 | 0.0059 |  |
| [CVE-2021-23992](https://patchblox.com/security/data/cve/CVE-2021-23992.md) | Routine | Thunderbird: Thunderbird did not check if the user ID associated with an OpenPGP key has a valid self signature. | 4.3 | 0.0048 |  |
| [CVE-2021-23993](https://patchblox.com/security/data/cve/CVE-2021-23993.md) | Routine | Thunderbird: An attacker may perform a DoS attack to prevent a user from sending encrypted email to a correspondent. | 6.5 | 0.0042 |  |
| [CVE-2021-29948](https://patchblox.com/security/data/cve/CVE-2021-29948.md) | Routine | Thunderbird: Signatures are written to disk before and read during verification, which might be subject to a race… | 2.5 | 0.0029 |  |

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