CVE-2026-34479

high

Published 2026-04-10 · Modified 2026-04-16

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CVSS v3

7.5

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CVSS v4 NEW

6.9

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

VIR risk

7.5

Description

Apache Log4j 1 to Log4j 2 bridge: silent log event loss in Log4j1XmlLayout due to unescaped XML 1.0 forbidden characters

Predictions

Exploit likelihood

83%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

OS impact

OS	Version	Status	Fixed in
debian	forky	fixed	`0`
debian	sid	fixed	`0`
debian	trixie	fixed	`0`
debian	bookworm	fixed	`0`
debian	bullseye	fixed	`0`
sles		affected

Package impact

Ecosystem	Package	Vulnerable	Fixed
Maven	org.apache.logging.log4j:log4j-1.2-api	`>=2.7,<2.25.4`	`2.25.4`
Maven	org.apache.logging.log4j:log4j-1.2-api	`>=3.0.0-beta1,<=3.0.0-beta2`

Application impact

Vendor	Product	Versions	Fixed
apache	log4j	`{"startIncluding":"2.7","endExcluding":"2.25.4"}`	`2.25.4`
apache	log4j	`3.0.0`

References

CWEs

CWE-116

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.