CVE-2026-6665 (GCVE-0-2026-6665)

Vulnerability from cvelistv5 – Published: 2026-05-09 00:43 – Updated: 2026-05-09 00:43
VLAI?
Title
PgBouncer buffer overflow in SCRAM
Summary
The SCRAM code in PgBouncer before 1.25.2 did not check the return value of strlcat() correctly when building the contents of the SCRAM client-final-message. A malicious backend that sends a SCRAM server-final-message with a long nonce can trigger a stack overflow.
Severity ?
8.1 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE
  • CWE-121 - Stack-based Buffer Overflow
Assigner
References
Impacted products
Vendor Product Version
n/a PgBouncer Affected: 0 , < 1.25.2 (semver)
Credits
Thanks to HarutoKimura for finding and reporting this problem.
Show details on NVD website
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        "dateUpdated": "2026-05-09T00:43:46.762Z",
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        "shortName": "PostgreSQL"
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    "dateReserved": "2026-04-20T12:25:43.793Z",
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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.

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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.
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  • 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.



Detection rules are retrieved from Rulezet.