CVE-2021-46022Public exploit

Application crash via malformed recfile comment byte

Published Jan 14, 2022 · Updated Aug 4, 2024

Use-after-free in GNU Recutils 1.8.90 allows context-dependent attackers to crash recsel or recinf with a malformed recfile. The rec_parse_comment function passes a narrowed character to rec_buf_putc, causing input byte 0xff to be interpreted as EOF; teardown then reaches rec_mset_elem_destroy with an invalid or duplicate element pointer. The attack requires a user or calling process to parse an attacker-supplied recfile, and the demonstrated consequence is termination of the affected command.

CVSS severity5.5
Medium
EPSS probability0.97%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in GNU Recutils 1.8.90 allows context-dependent attackers to crash recsel or recinf with a malformed recfile. The rec_parse_comment function passes a narrowed character to rec_buf_putc, causing input byte 0xff to be interpreted as EOF; teardown then reaches rec_mset_elem_destroy with an invalid or duplicate element pointer. The attack requires a user or calling process to parse an attacker-supplied recfile, and the demonstrated consequence is termination of the affected command.

The record

CVE
CVE-2021-46022
Published
Jan 14, 2022
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-416, T1499.004
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 14, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

4.3NIST NVDAV:N/AC:M/Au:N/C:N/I:N/A:P
5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-416Use After Free
T1499.004Application or System Exploitation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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