CVE-2015-6525

high

Published 2015-08-24 · Modified 2026-05-06

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CVSS v3

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CVSS v4 NEW

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not yet in upstream

VIR risk

7.5

Description

Multiple integer overflows in the evbuffer API in Libevent 2.0.x before 2.0.22 and 2.1.x before 2.1.5-beta allow context-dependent attackers to cause a denial of service or possibly have other unspecified impact via "insanely large inputs" to the (1) evbuffer_add, (2) evbuffer_prepend, (3) evbuffer_expand, (4) exbuffer_reserve_space, or (5) evbuffer_read function, which triggers a heap-based buffer overflow or an infinite loop. NOTE: this identifier was SPLIT from CVE-2014-6272 per ADT3 due to different affected versions.

Predictions

Exploit likelihood

20%

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.

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OS impact

OS	Version	Status	Fixed in
debian	bookworm	fixed	`2.0.21-stable-2`
debian	bullseye	fixed	`2.0.21-stable-2`
debian	forky	fixed	`2.0.21-stable-2`
debian	sid	fixed	`2.0.21-stable-2`
debian	trixie	fixed	`2.0.21-stable-2`
debian	7.1	affected

Application impact

Vendor	Product	Versions
libevent_project	libevent	`2.0.1`
libevent_project	libevent	`2.0.2`
libevent_project	libevent	`2.0.3`
libevent_project	libevent	`2.0.4`
libevent_project	libevent	`2.0.5`
libevent_project	libevent	`2.0.6`
libevent_project	libevent	`2.0.7`
libevent_project	libevent	`2.0.8`
libevent_project	libevent	`2.0.9`
libevent_project	libevent	`2.0.10`
libevent_project	libevent	`2.0.11`
libevent_project	libevent	`2.0.12`
libevent_project	libevent	`2.0.13`
libevent_project	libevent	`2.0.14`
libevent_project	libevent	`2.0.15`
libevent_project	libevent	`2.0.16`
libevent_project	libevent	`2.0.17`
libevent_project	libevent	`2.0.18`
libevent_project	libevent	`2.0.19`
libevent_project	libevent	`2.0.20`
libevent_project	libevent	`2.0.21`
libevent_project	libevent	`2.1.1`
libevent_project	libevent	`2.1.2`
libevent_project	libevent	`2.1.3`
libevent_project	libevent	`2.1.4`

References

CWEs

CWE-189

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

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