CVE-2025-54764
published 2025-10-20CVE-2025-54764: Mbed TLS before 3.6.5 allows a local timing attack against certain RSA operations, and direct calls to mbedtls_mpi_mod_inv or mbedtls_mpi_gcd.
PriorityP424medium6.2CVSS 3.1
AVLACLPRNUINSUCHINAN
EPSS
0.22%
12.6th percentile
Mbed TLS before 3.6.5 allows a local timing attack against certain RSA operations, and direct calls to mbedtls_mpi_mod_inv or mbedtls_mpi_gcd.
Affected
4 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| arm | mbed_tls | < 3.6.5 | 3.6.5 |
| debian | mbedtls | < mbedtls 3.6.5-0.1 (forky) | mbedtls 3.6.5-0.1 (forky) |
| mbed | mbedtls | >= 0 < 3.6.5-0.1~deb13u1 | 3.6.5-0.1~deb13u1 |
| mbed | mbedtls | >= 0 < 3.6.5-0.1 | 3.6.5-0.1 |
CVSS provenance
nvdv3.16.2MEDIUMCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
osv6.2MEDIUM
vendor_debian6.2MEDIUM
vendor_redhat6.2MEDIUM
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GHSA
GHSA-6237-9hpw-gcm6: Mbed TLS before 3
ghsa_unreviewed·2025-10-21
CVE-2025-54764 [MEDIUM] CWE-208 GHSA-6237-9hpw-gcm6: Mbed TLS before 3
Mbed TLS before 3.6.5 allows a local timing attack against certain RSA operations, and direct calls to mbedtls_mpi_mod_inv or mbedtls_mpi_gcd.
OSV
CVE-2025-54764: Mbed TLS before 3
osv·2025-10-20·CVSS 6.2
CVE-2025-54764 [MEDIUM] CVE-2025-54764: Mbed TLS before 3
Mbed TLS before 3.6.5 allows a local timing attack against certain RSA operations, and direct calls to mbedtls_mpi_mod_inv or mbedtls_mpi_gcd.
Red Hat
mbedtls: Mbedtls timing attacks in RSA operations
vendor_redhat·2025-10-20·CVSS 6.2
CVE-2025-54764 [MEDIUM] CWE-208 mbedtls: Mbedtls timing attacks in RSA operations
mbedtls: Mbedtls timing attacks in RSA operations
Mbed TLS before 3.6.5 allows a local timing attack against certain RSA operations, and direct calls to mbedtls_mpi_mod_inv or mbedtls_mpi_gcd.
Mbed TLS’s modular inversion routine and GCD routine are vulnerable to local timing attacks in multiple ways. Please see the linked mbed-tls advisory for technical details. When one of the vulnerable RSA functions is used, the vulnerability allows the attacker to fully recover the RSA private key. The side channels in GCD and modular inversion can be exploited by a local attacker.
Statement: A Moderate severity flaw was found in Mbed TLS, which is packaged in Red Hat community offerings (Fedora and EPEL). The Mbed TLS modular inversion routine (mbedtls_mpi_mod_inv) and GCD routine (mbedtls_mpi_gcd
Debian
CVE-2025-54764: mbedtls - Mbed TLS before 3.6.5 allows a local timing attack against certain RSA operation...
vendor_debian·2025·CVSS 6.2
CVE-2025-54764 [MEDIUM] CVE-2025-54764: mbedtls - Mbed TLS before 3.6.5 allows a local timing attack against certain RSA operation...
Mbed TLS before 3.6.5 allows a local timing attack against certain RSA operations, and direct calls to mbedtls_mpi_mod_inv or mbedtls_mpi_gcd.
Scope: local
bookworm: open
bullseye: open
forky: resolved (fixed in 3.6.5-0.1)
sid: resolved (fixed in 3.6.5-0.1)
trixie: resolved (fixed in 3.6.5-0.1~deb13u1)
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2025-54764 micropython: Mbedtls timing attacks in RSA operations [fedora-all]
bugzilla·2025-10-20·CVSS 6.2
CVE-2025-54764 [MEDIUM] CVE-2025-54764 micropython: Mbedtls timing attacks in RSA operations [fedora-all]
CVE-2025-54764 micropython: Mbedtls timing attacks in RSA operations [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
The following link provides references to all essential vulnerability management information. If something is wrong or missing, please contact a member of PSIRT.
https://spaces.redhat.com/display/PRODSEC/Vulnerability+Management+-+Essential+Documents+for+Engineering+Teams
Bugzilla
CVE-2025-54764 rust-psa-crypto-sys: Mbedtls timing attacks in RSA operations [fedora-42]
bugzilla·2025-10-20·CVSS 6.2
CVE-2025-54764 [MEDIUM] CVE-2025-54764 rust-psa-crypto-sys: Mbedtls timing attacks in RSA operations [fedora-42]
CVE-2025-54764 rust-psa-crypto-sys: Mbedtls timing attacks in RSA operations [fedora-42]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
The following link provides references to all essential vulnerability management information. If something is wrong or missing, please contact a member of PSIRT.
https://spaces.redhat.com/display/PRODSEC/Vulnerability+Management+-+Essential+Documents+for+Engineering+Teams
Discussion:
This message is a reminder that Fedora Linux 42 is nearing its end of life.
Fedora will stop maintaining and issuing updates for Fedora Linux 42 on 2026-05-13.
It is Fedora's policy to close all bug
Bugzilla
CVE-2025-54764 dolphin-emu: Mbedtls timing attacks in RSA operations [fedora-42]
bugzilla·2025-10-20·CVSS 6.2
CVE-2025-54764 [MEDIUM] CVE-2025-54764 dolphin-emu: Mbedtls timing attacks in RSA operations [fedora-42]
CVE-2025-54764 dolphin-emu: Mbedtls timing attacks in RSA operations [fedora-42]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
The following link provides references to all essential vulnerability management information. If something is wrong or missing, please contact a member of PSIRT.
https://spaces.redhat.com/display/PRODSEC/Vulnerability+Management+-+Essential+Documents+for+Engineering+Teams
Discussion:
This message is a reminder that Fedora Linux 42 is nearing its end of life.
Fedora will stop maintaining and issuing updates for Fedora Linux 42 on 2026-05-13.
It is Fedora's policy to close all bug reports
Bugzilla
CVE-2025-54764 mbedtls: Mbedtls timing attacks in RSA operations [epel-8]
bugzilla·2025-10-20·CVSS 6.2
CVE-2025-54764 [MEDIUM] CVE-2025-54764 mbedtls: Mbedtls timing attacks in RSA operations [epel-8]
CVE-2025-54764 mbedtls: Mbedtls timing attacks in RSA operations [epel-8]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
The following link provides references to all essential vulnerability management information. If something is wrong or missing, please contact a member of PSIRT.
https://spaces.redhat.com/display/PRODSEC/Vulnerability+Management+-+Essential+Documents+for+Engineering+Teams
Discussion:
Proposed as a Blocker for 43-final by Fedora user pbrobinson using the blocker tracking app because:
mbedtls 3.6.5 is a security release. It has a number of CVEs, there's one rated HIGH [1] (Red Hat doesn't rate
2025-10-20
Published