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CVE-2025-49087: mbed mbedtls Covert Timing Channel

CVSS: 4.0v3.1MediumAnalyzed
AliasesALPINE-CVE-2025-49087UBUNTU-CVE-2025-49087DEBIAN-CVE-2025-49087
Published 20-07-2025Last modified 21-07-2025
Open JSON

Vulnerability summary

CVE-2025-49087 is a medium (CVSS 4.0) Covert Timing Channel vulnerability in mbed mbedtls. EPSS estimates a 0.44% chance of exploitation in the next 30 days, higher than 36.9% of scored vulnerabilities. 1 public exploit is recorded.

Overall risk
26/100
0100
Medium · default modelHow is this calculated?
CVSS score
4.0/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.44%
0%100%
Low · +0.04 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1github

Advisory lineage

Upstream 0 · Downstream 1 · Related 1
OPENSUSE-SU-2026:21144-1

Timeline

  1. 20-07-2025
    PublishedVulnerability first disclosed.
  2. 21-07-2025
    Last modifiedVulnerability information updated.

Description

In Mbed TLS 3.6.1 through 3.6.3 before 3.6.4, a timing discrepancy in block cipher padding removal allows an attacker to recover the plaintext when PKCS#7 padding mode is used.

CVSS metrics

5 scores · 5 sources · 1 version

EPSS trend

Probability

0.44%

Chance of exploitation in the next 30 days

Percentile

37%

Versus all other CVEs

30-day change

+0.04 pp

From 0.40% on 20-09-2026

20-09-202620-10-2026
EPSS score
0.44%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

1 found
  • githubUnverified

    Mbedtls Docs

    Maturity: poc

Weaknesses

CWE · root cause

Affected systems

Alpine1 product
  • mbedtls< 3.6.4-r0
Debian1 product
  • mbedtls< 3.6.4-1
Mbed1 product
Trustedfirmware1 product
Ubuntu1 product
  • mbedtlsAll versions (No fix recorded)

5 vendors · 5 products

References

6 links