CVE-2026-9828CWE-502

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

Low · published May 28, 2026

CVSS v4.0
2.9
EPSS
1%
Percentile
45.0
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
2.9 · LOW
Vector
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
EPSS
0.00545 · 45.0th percentile
Weakness
CWE-502 · Deserialization of Untrusted Data
Published
2026-05-28T12:52Z
EPSS history
Timeline
  • 28 MAY 12:52Z
    Logback deserialization whitelist bypass for java.lang and java.util
    cvelistv5