How severe is CVE-2013-4623?

CVE-2013-4623 has a CVSS 2.0 base score of 4.3, rated medium severity.

Is CVE-2013-4623 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2013-4623?

CVE-2013-4623 primarily affects Polarssl. In total, 17 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2013-4623?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2013-4623 published?

CVE-2013-4623 was published on 2013-09-30 and last updated on 2026-06-16.

CVE-2013-4623

CVE-2013-4623 is a medium-severity vulnerability in Polarssl with a CVSS 2.0 base score of 4.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 2.0 base score 4.3)
EPSS exploit prediction: 2% (77th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Polarssl
Published: 2013-09-30
Last modified: 2026-06-16

Description

The x509parse_crt function in x509.h in PolarSSL 1.1.x before 1.1.7 and 1.2.x before 1.2.8 does not properly parse certificate messages during the SSL/TLS handshake, which allows remote attackers to cause a denial of service (infinite loop and CPU consumption) via a certificate message that contains a PEM encoded certificate.

Frequently asked questions

What is CVE-2013-4623?: The x509parse_crt function in x509.h in PolarSSL 1.1.x before 1.1.7 and 1.2.x before 1.2.8 does not properly parse certificate messages during the SSL/TLS handshake, which allows remote attackers to cause a denial of service (infinite loop and CPU consumption) via a certificate message that contains a PEM encoded certificate.
How severe is CVE-2013-4623?: CVE-2013-4623 has a CVSS 2.0 base score of 4.3, rated medium severity.
Is CVE-2013-4623 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2013-4623?: CVE-2013-4623 primarily affects Polarssl. In total, 17 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2013-4623?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2013-4623 published?: CVE-2013-4623 was published on 2013-09-30 and last updated on 2026-06-16.

References

Affected products (17)

cpe:2.3:a:polarssl:polarssl:1.1.0:*:*:*:*:*:*:*
cpe:2.3:a:polarssl:polarssl:1.1.0:rc0:*:*:*:*:*:*
cpe:2.3:a:polarssl:polarssl:1.1.0:rc1:*:*:*:*:*:*
cpe:2.3:a:polarssl:polarssl:1.1.1:*:*:*:*:*:*:*
cpe:2.3:a:polarssl:polarssl:1.1.2:*:*:*:*:*:*:*
cpe:2.3:a:polarssl:polarssl:1.1.3:*:*:*:*:*:*:*
cpe:2.3:a:polarssl:polarssl:1.1.4:*:*:*:*:*:*:*
cpe:2.3:a:polarssl:polarssl:1.1.5:*:*:*:*:*:*:*
cpe:2.3:a:polarssl:polarssl:1.1.6:*:*:*:*:*:*:*
cpe:2.3:a:polarssl:polarssl:1.2.0:*:*:*:*:*:*:*
cpe:2.3:a:polarssl:polarssl:1.2.1:*:*:*:*:*:*:*
cpe:2.3:a:polarssl:polarssl:1.2.2:*:*:*:*:*:*:*
cpe:2.3:a:polarssl:polarssl:1.2.3:*:*:*:*:*:*:*
cpe:2.3:a:polarssl:polarssl:1.2.4:*:*:*:*:*:*:*
cpe:2.3:a:polarssl:polarssl:1.2.5:*:*:*:*:*:*:*
cpe:2.3:a:polarssl:polarssl:1.2.6:*:*:*:*:*:*:*
cpe:2.3:a:polarssl:polarssl:1.2.7:*:*:*:*:*:*:*

More vulnerabilities in Polarssl

CVE-2011-4574 — Critical (CVSS 9.8): PolarSSL versions prior to v1.1 use the HAVEGE random number generation algorithm. At its heart, this uses timing…
CVE-2014-9744 — High (CVSS 7.8): Memory leak in PolarSSL before 1.3.9 allows remote attackers to cause a denial of service (memory consumption) via a…
CVE-2014-8628 — High (CVSS 7.8): Memory leak in PolarSSL before 1.2.12 and 1.3.x before 1.3.9 allows remote attackers to cause a denial of service…
CVE-2015-1182 — High (CVSS 7.5): The asn1_get_sequence_of function in library/asn1parse.c in PolarSSL 1.0 through 1.2.12 and 1.3.x through 1.3.9 does…
CVE-2012-2130 — High (CVSS 7.4): A Security Bypass vulnerability exists in PolarSSL 0.99pre4 through 1.1.1 due to a weak encryption error when…
CVE-2015-8036 — Medium (CVSS 6.8): Heap-based buffer overflow in ARM mbed TLS (formerly PolarSSL) 1.3.x before 1.3.14 and 2.x before 2.1.2 allows remote…

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