CVE-2014-6272: Multiple integer overflows in the evbuffer API in Libevent 1.4.x before 1.4.15, 2.0.x before 2.0.22, and 2.1.x

This month

HIGH 7.5WATCHLISTMITIGATEDOWNGRADE

CVE-2014-6272 is a high-severity flaw (CVSS 7.5) affecting debian linux, libevent. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Multiple integer overflows in the evbuffer API in Libevent 1.4.x before 1.4.15, 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_expand, or (3) bufferevent_write function, which triggers a heap-based buffer overflow or an infinite loop. NOTE: this identifier has been SPLIT per

Why this priority

High severity
On your watchlist

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	7.5 (High)
EPSS exploit chance	2.1% (top 18%)
CISA exploited list	No
Weakness	CWE-189
Published	2015-08-24
Last modified	2026-06-17

Publisher (CNA): Debian GNU/Linux · Vendor: debian · libevent project

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2015-08-24 14:59 UTCPublished CVE record published
2026-06-17 00:12 UTCUpdated Record last modified

debian debian linux MITIGATE

Affected: 7.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 7.0

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

libevent project libevent DOWNGRADE

Affected: 1.4.0 · 1.4.1 · 1.4.2 · 1.4.3 · 1.4.4 · 1.4.5 · 1.4.6 · 1.4.7

Fixed in: no fixed release known

Safe to downgrade to: a release before 1.4.0

1. Check installed version

apt-cache policy libevent || rpm -q libevent || libevent --version

2. No fixed release: DOWNGRADE to a release before 1.4.0 (Debian / Ubuntu)

apt-cache madison libevent sudo apt install libevent=<VERSION_BEFORE_1.4.0> sudo apt-mark hold libevent

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list libevent sudo dnf downgrade libevent-<VERSION_BEFORE_1.4.0> sudo dnf versionlock add libevent

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2014-6272?

debian linux: mitigate or apply the listed mitigation; libevent: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2014-6272 being exploited?

CVE-2014-6272 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2014-6272 affect?

CVE-2014-6272 affects debian linux, libevent. Severity is high (CVSS 7.5). Multiple integer overflows in the evbuffer API in Libevent 1.4.x before 1.4.15, 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 "i

How urgent is CVE-2014-6272?

Priority 52/100. High severity; On your watchlist

Software pages

Debian vulnerabilities

Related CVEs

CVE-2023-42756 MEDIUM 4.4 UPGRADE MITIGATE A flaw was found in the Netfilter subsystem of the Linux kernel
CVE-2023-39417 HIGH 7.5 UPGRADE MITIGATE IN THE EXTENSION SCRIPT, a SQL Injection vulnerability was found in PostgreSQL if it uses @extowner@, @extsche
CVE-2026-111497 CRITICAL 9.8 EXPLOITED UPGRADE UPGRADE Google Brotli Unchecked Return Value Vulnerability
CVE-2025-38728 CRITICAL 9.1 UPGRADE MITIGATE In the Linux kernel, the following vulnerability has been resolved: smb3: fix for slab out of bounds on mount
CVE-2025-38204 HIGH 7.8 UPGRADE MITIGATE In the Linux kernel, the following vulnerability has been resolved: jfs: fix array-index-out-of-bounds read i

References

← Back to latest CVEs