GHSA-wv8q-qhhj-9h54: com.fasterxml.jackson.core:jackson-databind (CVE-2026-91776)

Package	Ecosystem	Affected	Fixed in
com.fasterxml.jackson.core:jackson-databind	Maven	>=2.0.0, <2.18.11 \|\| >=2.19.0, <2.21.7 \|\| >=2.22.0, <2.22.3	2.18.11, 2.21.7, 2.22.3
tools.jackson.core:jackson-databind	Maven	>=3.0.0, <3.1.7 \|\| >=3.2.0, <3.2.3	3.1.7, 3.2.3

Machine-written summary

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

Versions of jackson-databind from 2.0.0 up to but not including 2.18.11, 2.21.7 and 2.22.3, and from 3.0.0 up to but not including 3.1.7 and 3.2.3, are affected. Fixed versions are 2.18.11, 2.21.7, 2.22.3, 3.1.7 and 3.2.3, so upgrade to the fixed release in your line. The attacker needs to supply many distinct unknown type IDs to a long-lived mapper that uses name-based polymorphism with a defaultImpl fallback, which causes unbounded memory retention and possible denial of service. The source gives few details on the earliest affected version and no workaround is listed beyond upgrading.

Written 2 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
7.5	High	3.1	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H	CNA (HeroDevs)

CISA KEV Not listed.
EPSS 0.0049, the 42nd percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

31 Oct 2026, 14:16 UTC First seen by agentprime
31 Oct 2026, 14:16 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.