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CVE-2026-9828 (GCVE-0-2026-9828)

Vulnerability from cvelistv5 – Published: 2026-05-28 12:52 – Updated: 2026-05-29 08:07
VLAI
Title
Logback deserialization whitelist bypass for java.lang and java.util
Summary
Deserialization of untrusted data vulnerability in QOS.CH Sarl logback logback-core (HardenedObjectInputStream (logback-core) modules) allows Object Injection albeit heavily restricted. More precisely, an attacker able to influence serialized data sent to SimpleSocketServer or SimpleSSLSocketServer can instantiate objects from classes in the java.lang and java.util packages that are not explicitly blocked. Although deserialization is heavily restricted by HardenedObjectInputStream and no practical way to achieve remote code execution or significant privilege escalation has been identified, this issue constitutes a bypass of the intended security restrictions. This issue affects logback: through 1.5.32 inclusive.
Severity
2.9 (Low)
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/E:P/RE:L/U:Green
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-28 14:20 UTC
CWE
  • CWE-502 - Deserialization of untrusted data
Assigner
References
Impacted products
Vendor Product Version CPE status
QOS.CH Sarl logback Affected: 0 , ≤ 1.5.32 (maven)
Unaffected: 1.5.33
guessed Create a notification for this product.
Date Public
2026-05-28 07:47
Credits
York Shen https://github.com/york-shen
Show details on NVD website
To clipboard 

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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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  • 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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