CVE-2026-633848.7HighCWE-190

CVE-2026-63384: Libevent: `evtag_unmarshal_header()` decodes a wire `uint32` length into a signed `int` return value.

libevent

Affected: libevent · Exploitation: unlikely (under 1%)

Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.

0.5%probability of exploitation in the next 30 days

42nd percentile

050100

Higher than 42% of scored CVEs

8.7HighCVSS 4.0

LowMediumHighCrit.

DescriptionCVE.org

Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, libevent has an incorrect integer conversion in event_tagging.c when evtag_unmarshal_header uses evtag_decode_int to decode an attacker-controlled uint32 payload length and returns it as a signed int. Values above INT_MAX become negative or truncated, and evtag_unmarshal_string can use the converted value in allocation sizing, producing a wrapped large allocation request and denial of service. This issue is fixed in versions 2.1.13 and 2.2.2-alpha.

Affected products1

From the CVE record. A product or version that is not listed is unknown, not unaffected.

libevent · libevent>= 2.2.0-alpha, < 2.2.2-alpha; < 2.1.13

On the Atlas

Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.

Open the Atlas

Exploitation: Unlikely (under 1%). EPSS under 1%, or no score yet.
CISA KEV: Not listed
Public check: No public nuclei template
Weakness: Integer Overflow · Memory Corruption
Vendor: libevent
Published: August 2026
Band: Unlikely (under 1%), August 2026

CoverageNo articles yet

No CyberSIXT article names CVE-2026-63384 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.