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Fencer Intel
low 2.9

CVE-2026-9828 json

Logback deserialization whitelist bypass for java.lang and java.util

published 5mo ago modified 16d ago also GHSA-p47f-322f-whfh , EUVD-2026-32895

cvss
2.9
version 4.0, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 31%
public exploits
0
none known

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.

Patch / fix

  • maven ch.qos.logback:logback-core 1.5.33
  • QOS.CH Sarl logback 1.5.33
  • logback Debian 14 1:1.6.3-1

debian advisories DEBIAN-CVE-2026-9828

  • xmvn SLE Module for Development Tools 15 SP7, SLE High Performance Computing 15 SP5-ESPOS, SLE High Performance Computing 15 SP4-ESPOS +8 more 4.3.0-150200.3.33.1
  • maven SLE Module for Development Tools 15 SP7, SLE High Performance Computing 15 SP5-ESPOS, SLE High Performance Computing 15 SP4-ESPOS +8 more 3.10.0-150200.4.36.1
  • slf4j SLE Module for Development Tools 15 SP7, SLE Module for Basesystem 15 SP7, SLE High Performance Computing 15 SP5-ESPOS +9 more 2.0.20-150200.3.7.1
  • jline3 SLE Module for Development Tools 15 SP7, SLE High Performance Computing 15 SP5-ESPOS, SLE High Performance Computing 15 SP4-ESPOS +8 more 3.30.17-150200.5.11.1
  • methanol SLE Module for Development Tools 15 SP7, SLE High Performance Computing 15 SP5-ESPOS, SLE High Performance Computing 15 SP4-ESPOS +8 more 1.9.0-150200.5.3.1
  • aqute-bnd SLE Module for Development Tools 15 SP7, SLE High Performance Computing 15 SP5-ESPOS, SLE High Performance Computing 15 SP4-ESPOS +8 more 6.4.1-150200.3.16.1
  • xmvn-mojo SLE Module for Development Tools 15 SP7, SLE High Performance Computing 15 SP5-ESPOS, SLE High Performance Computing 15 SP4-ESPOS +8 more 4.3.0-150200.3.33.1
  • xmvn-tools SLE Module for Development Tools 15 SP7, SLE High Performance Computing 15 SP5-ESPOS, SLE High Performance Computing 15 SP4-ESPOS +8 more 4.3.0-150200.3.33.1

suse advisories SUSE-SU-2026:5189-1

  • logback openSUSE Tumbleweed 1.5.34-2.1

opensuse advisories openSUSE-SU-2026:11016-1

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-9828 updated cvss 4.8

logback: Logback: Object injection via deserialization of untrusted data

  • Red Hat All currently supported Red Hat products
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
5mo ago

Exploit prediction

0.37% chance of exploitation in the next 30 days, higher than 31% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by version score vector
CNA 4.0 2.9 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
CNA 4.0 2.9 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/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:L/U:Green

Affected packages

ecosystem package affected fixed in
maven ch.qos.logback:logback-core
<1.5.33
1.5.33

Affected products

  • QOS.CH Sarl logback

Classification

Weakness
  • CWE-502 Deserialization of Untrusted Data

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.