CVE-2021-43618Public exploitNetwork attack vector

Application crash via raw integer size overflow

Published Nov 15, 2021 · Updated Aug 4, 2024

Buffer overflow in GNU GMP 6.2.1 and earlier allows remote attackers to crash 32-bit applications via crafted raw-integer input. In mpz/inp_raw.c, abs_csize multiplied by eight wraps while calculating abs_xsize, causing MPZ_NEWALLOC to reserve too little space and placing the read pointer before the allocation. Exposure requires a 32-bit process that passes attacker-controlled data to mpz_inp_raw; the demonstrated consequence is process termination by segmentation fault.

CVSS severity7.5
High
EPSS probability3.71%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Buffer overflow in GNU GMP 6.2.1 and earlier allows remote attackers to crash 32-bit applications via crafted raw-integer input. In mpz/inp_raw.c, abs_csize multiplied by eight wraps while calculating abs_xsize, causing MPZ_NEWALLOC to reserve too little space and placing the read pointer before the allocation. Exposure requires a 32-bit process that passes attacker-controlled data to mpz_inp_raw; the demonstrated consequence is process termination by segmentation fault.

The record

CVE
CVE-2021-43618
Published
Nov 15, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-190, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 15, 2021CVE 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 vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.0NIST NVDAV:N/AC:L/Au:N/C:N/I:N/A:P
6.2Oracle LinuxCVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/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)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-190Integer Overflow or Wraparound
T1499.004Endpoint Denial of Service: Application 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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