CVE-2025-52497
published 2025-07-04CVE-2025-52497: Mbed TLS before 3.6.4 has a PEM parsing one-byte heap-based buffer underflow, in mbedtls_pem_read_buffer and two mbedtls_pk_parse functions, via untrusted PEM…
PriorityP422medium4.8CVSS 3.1
AVNACHPRNUINSUCLINAL
EPSS
0.28%
19.4th percentile
Mbed TLS before 3.6.4 has a PEM parsing one-byte heap-based buffer underflow, in mbedtls_pem_read_buffer and two mbedtls_pk_parse functions, via untrusted PEM input.
Affected
10 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| arm | mbed_tls | < 3.6.4 | 3.6.4 |
| debian | mbedtls | < mbedtls 2.16.9-0.1+deb11u2 (bullseye) | mbedtls 2.16.9-0.1+deb11u2 (bullseye) |
| mbed | mbedtls | < 3.6.4 | 3.6.4 |
| mbed | mbedtls | >= 0 < 2.16.9-0.1+deb11u2 | 2.16.9-0.1+deb11u2 |
| mbed | mbedtls | >= 0 < 3.6.4-1 | 3.6.4-1 |
| mbed | mbedtls | >= 0 < 3.6.4-1 | 3.6.4-1 |
| mbed | mbedtls | >= 0 < 2.8.0-1ubuntu0.1~esm1 | 2.8.0-1ubuntu0.1~esm1 |
| mbed | mbedtls | >= 0 < 2.16.4-1ubuntu2+esm1 | 2.16.4-1ubuntu2+esm1 |
| mbed | mbedtls | >= 0 < 2.28.0-1ubuntu0.1~esm1 | 2.28.0-1ubuntu0.1~esm1 |
| mbed | mbedtls | >= 0 < 2.28.8-1ubuntu0.1~esm1 | 2.28.8-1ubuntu0.1~esm1 |
CVSS provenance
nvdv3.14.8MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
osv9.8CRITICAL
vendor_ubuntu9.8CRITICAL
vendor_debian4.8MEDIUM
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OSV
mbedtls vulnerabilities
osv·2026-03-25·CVSS 9.8
CVE-2021-44732 [CRITICAL] mbedtls vulnerabilities
mbedtls vulnerabilities
It was discovered that Mbed TLS incorrectly handled memory allocation
failures. A remote attacker could possibly use this issue to crash
the program. This issue only affected Ubuntu 18.04 LTS and Ubuntu
20.04 LTS. (CVE-2021-44732)
Jonathan Winzig discovered that Mbed TLS incorrectly handled crafted
inputs. A remote attacker could possibly use this issue to crash the
program, resulting in a denial of service. This issue only affected
Ubuntu 18.04 LTS, Ubuntu 20.04 LTS, Ubuntu 22.04 LTS. (CVE-2024-23775)
It was discovered that Mbed TLS incorrectly handled the TLS
handshake. A remote attacker could possibly use this issue to
break the security guarantees of the TLS handshake.
(CVE-2025-27810)
Linh Le and Ngan Nguyen discovered that Mbed TLS incorrectly
documented t
GHSA
GHSA-3p24-8mw5-x2hx: Mbed TLS before 3
ghsa_unreviewed·2025-07-04
CVE-2025-52497 [MEDIUM] CWE-193 GHSA-3p24-8mw5-x2hx: Mbed TLS before 3
Mbed TLS before 3.6.4 has a PEM parsing one-byte heap-based buffer underflow, in mbedtls_pem_read_buffer and two mbedtls_pk_parse functions, via untrusted PEM input.
OSV
CVE-2025-52497: Mbed TLS before 3
osv·2025-07-04·CVSS 4.8
CVE-2025-52497 [MEDIUM] CVE-2025-52497: Mbed TLS before 3
Mbed TLS before 3.6.4 has a PEM parsing one-byte heap-based buffer underflow, in mbedtls_pem_read_buffer and two mbedtls_pk_parse functions, via untrusted PEM input.
Ubuntu
Mbed TLS vulnerabilities
vendor_ubuntu·2026-03-25·CVSS 9.8
CVE-2025-27810 [CRITICAL] Mbed TLS vulnerabilities
Title: Mbed TLS vulnerabilities
Summary: Several security issues were fixed in mbedtls.
It was discovered that Mbed TLS incorrectly handled memory allocation
failures. A remote attacker could possibly use this issue to crash
the program. This issue only affected Ubuntu 18.04 LTS and Ubuntu
20.04 LTS. (CVE-2021-44732)
Jonathan Winzig discovered that Mbed TLS incorrectly handled crafted
inputs. A remote attacker could possibly use this issue to crash the
program, resulting in a denial of service. This issue only affected
Ubuntu 18.04 LTS, Ubuntu 20.04 LTS, Ubuntu 22.04 LTS. (CVE-2024-23775)
It was discovered that Mbed TLS incorrectly handled the TLS
handshake. A remote attacker could possibly use this issue to
break the security guarantees of the TLS handshake.
(CVE-2025-27810)
Linh Le
Debian
CVE-2025-52497: mbedtls - Mbed TLS before 3.6.4 has a PEM parsing one-byte heap-based buffer underflow, in...
vendor_debian·2025·CVSS 4.8
CVE-2025-52497 [MEDIUM] CVE-2025-52497: mbedtls - Mbed TLS before 3.6.4 has a PEM parsing one-byte heap-based buffer underflow, in...
Mbed TLS before 3.6.4 has a PEM parsing one-byte heap-based buffer underflow, in mbedtls_pem_read_buffer and two mbedtls_pk_parse functions, via untrusted PEM input.
Scope: local
bookworm: open
bullseye: resolved (fixed in 2.16.9-0.1+deb11u2)
forky: resolved (fixed in 3.6.4-1)
sid: resolved (fixed in 3.6.4-1)
trixie: resolved (fixed in 3.6.4-1)
No detection rules found.
No public exploits indexed.
2025-07-04
Published