CVE-2021-33938Public exploitNetwork attack vector

Process crash via unchecked recommendsmap indexing

Published Sep 2, 2021 · Updated Aug 4, 2024

Heap-buffer overflow in openSUSE libsolv before 0.7.17 allows remote attackers to crash dependency-solving processes via crafted solver data. In prune_to_recommended in src/policy.c, MAPSET and MAPTST use an unchecked provider identifier to index recommendsmap, reading or writing beyond its heap allocation. Reachability depends on a consuming application passing attacker-controlled solver input into dependency resolution; demonstrated effects are process aborts and service interruption, with no reported data disclosure or modification.

CVSS severity7.5
High
EPSS probability1.42%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Heap-buffer overflow in openSUSE libsolv before 0.7.17 allows remote attackers to crash dependency-solving processes via crafted solver data. In prune_to_recommended in src/policy.c, MAPSET and MAPTST use an unchecked provider identifier to index recommendsmap, reading or writing beyond its heap allocation. Reachability depends on a consuming application passing attacker-controlled solver input into dependency resolution; demonstrated effects are process aborts and service interruption, with no reported data disclosure or modification.

The record

CVE
CVE-2021-33938
Published
Sep 2, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-787, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 2, 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

7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
5.0NIST NVDAV:N/AC:L/Au:N/C:N/I:N/A:P

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-787Out-of-bounds Write
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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