8.8

CVE-2023-6787: Keycloak: session hijacking via re-authentication

Analyzed
AliasesCGA-j8x3-x77r-cvhvCGA-x428-93fm-jvhjGHSA-c9h6-v78w-52wj
Published 25-04-2024Last modified 11-11-2025

Vulnerability summary

CVE-2023-6787 is a high (CVSS 8.8) Improper Authentication vulnerability in redhat build_of_keycloak. EPSS estimates a 0.74% chance of exploitation in the next 30 days, higher than 54.2% of scored vulnerabilities.

Overall risk
35/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.8/10
010
High · v3.1 (NVD)
EPSS score
0.74%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 0 · Related 3
CGA-497W-V44M-5Q6RCGA-P2M6-2QW4-9J4GCGA-V9P7-G7QM-VGF7

Timeline

  1. 25-04-2024
    PublishedVulnerability first disclosed.
  2. 11-11-2025
    Last modifiedVulnerability information updated.

Description

A flaw was found in Keycloak that occurs from an error in the re-authentication mechanism within org.keycloak.authentication. This flaw allows hijacking an active Keycloak session by triggering a new authentication process with the query parameter "prompt=login," prompting the user to re-enter their credentials. If the user cancels this re-authentication by selecting "Restart login," an account takeover may occur, as the new session, with a different SUB, will possess the same SID as the previous session.

CVSS metrics

5 scores · 5 sources · 1 version

EPSS trend

Probability

0.74%

Chance of exploitation in the next 30 days

Percentile

54%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.74% on 23-09-2026

23-09-202623-10-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Redhat2 products
Chainguard1 product
  • keycloak< 24.0.3-r0
Org.keycloak1 product
  • keycloak-services< 22.0.10 | ≥ 23.0.0, < 24.0.3
Wolfi1 product
  • keycloak< 24.0.3-r0

4 vendors · 5 products

References

10 links