Go Programming Language 1.27.3
Go Programming Language 1.27.3, released October 19, 2026, fixes 19 CVEs in Go Programming Language. None of them is reported as exploited. Patch Radar priority: Urgent. The latest Go Programming Language is 1.27.4, which also fixes every one of these CVEs.
Superseded. The latest Go Programming Language is 1.27.4, which also fixes every CVE on this page. Install that instead.
Priority of the 19 CVEs
Applies to
| Product | Version |
|---|---|
| Go Programming Language | 1.27.3 |
CVEs this fix closes
| Priority | CVE | Title | CVSS | EPSS | Exploitation |
|---|---|---|---|---|---|
| Urgent | CVE-2026-56857 | Root.Mkdir(All) can follow junctions out of the root on Windows in os | 9.8 | 0.0055 | None reported |
| High | CVE-2026-97031 | Reject malformed ECH outer extension references in crypto/tls | 7.5 | 0.0072 | None reported |
| High | CVE-2026-94440 | Memory limit bypass when parsing MIME headers in net/textproto, mime/multipart | 7.5 | 0.0071 | None reported |
| High | CVE-2026-56866 | HTTP/1 client connection desynchronization after CONNECT rejection in net/http | 7.5 | 0.0060 | None reported |
| High | CVE-2026-33818 | Enforce maximum recursion depth in encoding/asn1 | 8.8 | 0.0057 | None reported |
| High | CVE-2026-56859 | Add recursion depth guard during decode in encoding/xml | 8.8 | 0.0057 | None reported |
| High | CVE-2026-56862 | Limit handshake messages we are willing to accept post-handshake in crypto/tls | 8.8 | 0.0057 | None reported |
| High | CVE-2026-56860 | Avoid quadratic complexity in resolvePath in net/url | 8.8 | 0.0055 | None reported |
| High | CVE-2026-46600 | Parsing an invalid SVCB or HTTPS RR can panic in golang.org/x/net/dns/dnsmessage | 7.5 | 0.0055 | None reported |
| High | CVE-2026-111943 | Go: CVE-2026-111943 Distrust compromised intermediate certificates in crypto/x509 | 8.1 | 0.0040 | None reported |
| High | CVE-2026-56858 | Fix Javascript regexp context tracking in html/template | 8.8 | 0.0031 | None reported |
| High | CVE-2026-56864 | Ignore unrelated, unauthenticated hashes in Lookup in golang.org/x/mod/sumdb | 7.5 | 0.0030 | None reported |
| High | CVE-2026-39822 | Root escape via symlink plus trailing slash in os | 8.2 | 0.0023 | None reported |
| High | CVE-2026-56865 | Fix transparency log tile verification bypass in golang.org/x/mod/sumdb/tlog | 8.4 | 0.0013 | None reported |
| High | CVE-2026-94447 | Checksum database bypass for golang.org/toolchain in cmd/go | 7.8 | 0.0010 | None reported |
| High | CVE-2026-94444 | Checksum bypass for golang.org/fips140 in cmd/go | 7.8 | 0.0010 | None reported |
| Routine | CVE-2026-42505 | Invoking Encrypted Client Hello privacy leak in crypto/tls | 5.3 | 0.0038 | None reported |
| Routine | CVE-2026-94448 | Reset context tracking on consecutive template expressions in html/template | 6.1 | 0.0029 | None reported |
| Routine | CVE-2026-97030 | Recognize yield as regexp preceder keyword in html/template | 6.1 | 0.0029 | None reported |
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