CVE-2026-63383

highpriority · track · 0EPSS 0.005 · 42 %ileDEFRRU

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

0.49% (42nd) EPSS

CVSS 7.5 · high

Is it mine?

18 products

Check your exposure

Who says so?

3 sources

fstec_bdu · cert_bund · certfr

EPSS · scored 2026-10-28

Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, libevent can read beyond a contiguous evbuffer region in event_tagging.c when decode_tag_internal requests at most five bytes from evbuffer_pullup but iterates using the full logical buffer length. A fragmented evbuffer containing a six-byte malformed tag can therefore advance past the pullup window and trigger an out-of-bounds read, which can crash a process that decodes attacker-controlled tagged RPC data. This issue is fixed in versions 2.1.13 and 2.2.2-alpha.

cvss

Technical severity, 0–10. One row per scoring source.

8.7

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.6–8.7

v3.17.5highAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU

v4.08.7highCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/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:Xsecondary · security-advisories@github.com

v4.06.6mediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/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:Xsecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: poc · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-125USCWE-125US

affected products (18)

Products and version ranges known to be affected.

Amazon Linux 2all versionscert_bundDEcpe:/o:amazon:linux_2:-
Debian Linuxall versionscert_bundDEcpe:/o:debian:debian_linux:-
Fedora Linuxall versionscert_bundDEcpe:/o:fedoraproject:fedora:-
IBM AIX 7.2all versionscert_bundDEcpe:/o:ibm:aix:7.2
IBM AIX 7.3all versionscert_bundDEcpe:/o:ibm:aix:7.3
IBM MQ Operatorall versionscert_bundDEcpe:/a:ibm:mq:operator
IBM QRadar SIEMall versionscert_bundDEcpe:/a:ibm:qradar_siem:-
IBM VIOS 4.1all versionscert_bundDEcpe:/a:ibm:vios:4.1
IBM iall versionscert_bundDEcpe:/o:ibm:i:-
Oracle Linuxall versionscert_bundDEcpe:/o:oracle:linux:-
RESF Rocky Linuxall versionscert_bundDEcpe:/o:resf:rocky_linux:-
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
Red Hat Enterprise Linux 9all versionscert_bundDEcpe:/o:redhat:enterprise_linux:9
SUSE Linuxall versionscert_bundDEcpe:/o:suse:suse_linux:-
SUSE openSUSEall versionscert_bundDEcpe:/o:suse:opensuse:-
Ubuntu Linuxall versionscert_bundDEcpe:/o:canonical:ubuntu_linux:-
Libevent project Libevent≤ 2.1.12fstec_bduRU
Libevent project Libevent≤ 2.2.1-alphafstec_bduRU

advisories (3)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2026-3419Red Hat Enterprise Linux (corosync, libevent, libsoup): Mehrere SchwachstellenDeutsch2026-09-16csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Red Hat Enterprise Linux ausnutzen, um beliebigen Code auszuführen, Sicherheitsmaßnahmen zu umgehen, Daten zu manipulieren oder offenzulegen oder Denial-of-Service-Zustände herbeizuführen.
CERTFR-2026-AVI-1336Multiples vulnérabilités dans les produits IBMFrançais2026-10-16vendor · certfrFR
CERTFR-2026-AVI-1378Multiples vulnérabilités dans les produits IBMFrançais2026-10-23vendor · certfrFR

also known as (2)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

fstec_bdu cert_bund certfr NVD CVE.org MITRE

published 2026-08-20modified 2026-10-26

references (5) nvd

External citations — patches, advisories, analysis.

scry

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