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CVE-2026-18238 (GCVE-0-2026-18238)

Vulnerability from cvelistv5 – Published: 2026-09-05 18:51 – Updated: 2026-09-08 15:17
VLAI
Title
OOBR in rpcap client in libpcap before 1.10.7
Summary
The rpcap client code that processes a RPCAP_MSG_PACKET message received from the server incorrectly validates its headers. A malicious server can send a crafted message and cause the client to treat up to 20 bytes of the client process memory beyond the end of the buffer as if it was a part of the captured packet.
Severity
5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-08 15:17 UTC
CWE
  • CWE-1288 - Improper Validation of Consistency within Input
  • CWE-126 - Buffer Over-read
Assigner
References
Impacted products
Vendor Product Version CPE status
The Tcpdump Group libpcap Affected: 1.8.x
Affected: 1.9.x
Affected: 1.10.x , < 1.10.7 (semver)
guessed Create a notification for this product.
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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