How severe is CVE-2023-36632?

CVE-2023-36632 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-2023-36632 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-36632?

CVE-2023-36632 affects Python. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-36632?

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-2023-36632 published?

CVE-2023-36632 was published on 2023-06-25 and last updated on 2026-06-17.

CVE-2023-36632

CVE-2023-36632 is a high-severity vulnerability in Python with a CVSS 3.x base score of 7.5. 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-674.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 2% (73rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-674
Affected product: Python
Published: 2023-06-25
Last modified: 2026-06-17

Description

The legacy email.utils.parseaddr function in Python through 3.11.4 allows attackers to trigger "RecursionError: maximum recursion depth exceeded while calling a Python object" via a crafted argument. This argument is plausibly an untrusted value from an application's input data that was supposed to contain a name and an e-mail address. NOTE: email.utils.parseaddr is categorized as a Legacy API in the documentation of the Python email package. Applications should instead use the email.parser.BytesParser or email.parser.Parser class. NOTE: the vendor's perspective is that this is neither a vulnerability nor a bug. The email package is intended to have size limits and to throw an exception when limits are exceeded; they were exceeded by the example demonstration code.

Frequently asked questions

What is CVE-2023-36632?: The legacy email.utils.parseaddr function in Python through 3.11.4 allows attackers to trigger "RecursionError: maximum recursion depth exceeded while calling a Python object" via a crafted argument. This argument is plausibly an untrusted value from an application's input data that was supposed to contain a name and an e-mail address. NOTE: email.utils.parseaddr is categorized as a Legacy API in the documentation of the Python email package. Applications should instead use the email.parser.BytesParser or email.parser.Parser class. NOTE: the vendor's perspective is that this is neither a vulnerability nor a bug. The email package is intended to have size limits and to throw an exception when limits are exceeded; they were exceeded by the example demonstration code.
How severe is CVE-2023-36632?: CVE-2023-36632 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-2023-36632 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-36632?: CVE-2023-36632 affects Python. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-36632?: 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-2023-36632 published?: CVE-2023-36632 was published on 2023-06-25 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:python:python:*:*:*:*:*:*:*:*

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Threat intelligence

Threat-intel indicators referencing this CVE:

49.229.102.187 (ipv4-addr)
41.63.62.103 (ipv4-addr)
203.192.232.180 (ipv4-addr)
177.53.215.134 (ipv4-addr)
141.109.168.26 (ipv4-addr)
141.109.168.107 (ipv4-addr)
125.212.235.194 (ipv4-addr)
120.28.109.188 (ipv4-addr)