CVE-2019-5010

CVE-2019-5010 is a high-severity vulnerability in Python with a CVSS 3.x base score of 7.5. Its EPSS exploit-prediction score of 21% places it in the 97th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-476.

Key facts

• Severity: High (CVSS 3.x base score 7.5)
• CVSS v2: 5.0
• EPSS exploit prediction: 21% (97th percentile)
• Actively exploited: Not listed in CISA KEV
• Weakness: CWE-476
• Affected product: Python
• Published: 2019-10-31
• Last modified: 2026-06-17

Description

An exploitable denial-of-service vulnerability exists in the X509 certificate parser of Python.org Python 2.7.11 / 3.6.6. A specially crafted X509 certificate can cause a NULL pointer dereference, resulting in a denial of service. An attacker can initiate or accept TLS connections using crafted certificates to trigger this vulnerability.

Frequently asked questions

What is CVE-2019-5010?

An exploitable denial-of-service vulnerability exists in the X509 certificate parser of Python.org Python 2.7.11 / 3.6.6. A specially crafted X509 certificate can cause a NULL pointer dereference, resulting in a denial of service. An attacker can initiate or accept TLS connections using crafted certificates to trigger this vulnerability.

How severe is CVE-2019-5010?

CVE-2019-5010 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2019-5010 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 21% (97th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-5010?

CVE-2019-5010 primarily affects Python. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2019-5010?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2019-5010 published?

CVE-2019-5010 was published on 2019-10-31 and last updated on 2026-06-17.

References

• http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00040.html
• https://access.redhat.com/errata/RHSA-2019:3520
• https://access.redhat.com/errata/RHSA-2019:3725
• https://lists.apache.org/thread.html/r1b103833cb5bc8466e24ff0ecc5e75b45a705334ab6a444e64e840a0%40%3Cissues.bookkeeper.apache.org%3E
• https://lists.debian.org/debian-lts-announce/2020/07/msg00011.html
• https://lists.debian.org/debian-lts-announce/2020/08/msg00034.html
• https://security.gentoo.org/glsa/202003-26
• https://talosintelligence.com/vulnerability_reports/TALOS-2019-0758

Affected products (14)

• cpe:2.3:a:python:python:*:*:*:*:*:*:*:*
• cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:*
• cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_eus:8.1:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_eus:8.2:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_eus:8.4:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_eus:8.6:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_server_aus:8.2:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_server_aus:8.4:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_server_aus:8.6:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_server_tus:8.2:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_server_tus:8.4:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_server_tus:8.6:*:*:*:*:*:*:*

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Other CWE-476 (NULL Pointer Dereference) vulnerabilities

• CVE-2022-36648 — Critical (CVSS 10.0): The hardware emulation in the of_dpa_cmd_add_l2_flood of rocker device model in QEMU, as used in 7.0.0 and earlier,…
• CVE-2020-14500 — Critical (CVSS 10.0): Secomea GateManager all versions prior to 9.2c, An attacker can send a negative value and overwrite arbitrary data.
• CVE-2010-2495 — Critical (CVSS 10.0): The pppol2tp_xmit function in drivers/net/pppol2tp.c in the L2TP implementation in the Linux kernel before 2.6.34 does…
• CVE-2026-46195 — Critical (CVSS 9.8): In the Linux kernel, the following vulnerability has been resolved: smb: client: validate dacloffset before building…
• CVE-2026-31657 — Critical (CVSS 9.8): In the Linux kernel, the following vulnerability has been resolved: batman-adv: hold claim backbone gateways by…
• CVE-2026-31436 — Critical (CVSS 9.8): In the Linux kernel, the following vulnerability has been resolved: dmaengine: idxd: fix possible wrong descriptor…

Browse all CWE-476 (NULL Pointer Dereference) vulnerabilities →

Threat intelligence

Threat-intel indicators referencing this CVE:

• 203.192.232.180 (ipv4-addr)
• 177.53.215.134 (ipv4-addr)
• 120.28.109.188 (ipv4-addr)
• 5.99.196.202 (ipv4-addr)
• 121.164.135.251 (ipv4-addr)
• 120.224.15.67 (ipv4-addr)
• 222.88.237.152 (ipv4-addr)