CVE-2023-2603

Heap overwrite via 32-bit length overflow

Published Jun 6, 2023 · Updated Dec 2, 2025

Integer overflow in libcap allows local users to overwrite heap memory by supplying a string near 4 GiB during 32-bit execution. The _libcap_strdup function adds header overhead to strlen(old) in a 32-bit size_t before checking the result, so the wrapped length drives an undersized allocation followed by strcpy. Reachability requires a calling process in 32-bit compatibility mode to accept an attacker-controlled string near 4 GiB; exploitation can crash or corrupt that process.

CVSS severity7.8
High
EPSS probability0.58%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Integer overflow in libcap allows local users to overwrite heap memory by supplying a string near 4 GiB during 32-bit execution. The _libcap_strdup function adds header overhead to strlen(old) in a 32-bit size_t before checking the result, so the wrapped length drives an undersized allocation followed by strcpy. Reachability requires a calling process in 32-bit compatibility mode to accept an attacker-controlled string near 4 GiB; exploitation can crash or corrupt that process.

The record

CVE
CVE-2023-2603
Published
Jun 6, 2023
Updated
Dec 2, 2025
Vendor
Andrew G. Morgan
Product
libcap
Classifications
CWE-190
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 6, 2023CVE publishedPublication date reported by the CVE source.
  2. Dec 2, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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  1. Affected versionversion=NA

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Andrew G. Morgan · libcapversion=NA

Published CVSS scores

4.4Amazon LinuxCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L
7.8CISA-ADPCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
7.8NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
7.8CanonicalCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-190Integer Overflow or Wraparound

Public exploit references

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Technologies

Your stack

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Your stack

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