GHSA-4w3g-jfj2-cw2q: github.com/go-jose/go-jose/v4 (CVE-2026-116585)

Package	Ecosystem	Affected	Fixed in
github.com/go-jose/go-jose/v4	Go	<4.1.5	4.1.5
github.com/go-jose/go-jose/v3	Go	<=3.0.5	No fixed version yet

Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

Go JOSE v4 versions before 4.1.5 and v3 versions up to and including 3.0.5 are vulnerable to a panic when decrypting ciphertexts that use the A128CBC-HS256, A192CBC-HS384, or A256CBC-HS512 content encryption algorithms. Any application that decrypts untrusted ciphertexts with these algorithms can be caused to crash, which is a denial of service. Upgrade github.com/go-jose/go-jose/v4 to 4.1.5; no fixed version is listed for v3. For v4, if the CBC-HMAC modes are not needed, omit them from the allowed ContentEncryption algorithms passed to the parse functions.

Written 1 Nov 2026.

Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

Severity and exploitation

Score	Rating	CVSS	Vector	Source
6.9	Medium	4.0	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N	CNA (GitHub_M)

CISA KEV Not listed.
EPSS 0.0026, the 18th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

26 Oct 2026, 21:06 UTC Confirmed by the CVE List
31 Oct 2026, 14:11 UTC First seen by agentprime
31 Oct 2026, 14:11 UTC Confirmed by OSV

Sources

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.