How severe is CVE-2025-53628?

CVE-2025-53628 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2025-53628 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-53628?

CVE-2025-53628 affects Yhirose Cpp-httplib. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-53628?

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.

Does CVE-2025-53628 have an EU (EUVD) identifier?

Yes. CVE-2025-53628 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-21053.

When was CVE-2025-53628 published?

CVE-2025-53628 was published on 2025-07-10 and last updated on 2026-06-17.

CVE-2025-53628

CVE-2025-53628 is a high-severity vulnerability in Yhirose Cpp-httplib with a CVSS 3.x base score of 8.8. 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-444.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v4: 6.3
EPSS exploit prediction: 0% (36th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-21053
Weakness: CWE-444
Affected product: Yhirose Cpp-httplib
Published: 2025-07-10
Last modified: 2026-06-17

Description

cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.20.1, cpp-httplib does not have a limit for a unique line, permitting an attacker to explore this to allocate memory arbitrarily. This vulnerability is fixed in 0.20.1. NOTE: This vulnerability is related to CVE-2025-53629.

Frequently asked questions

What is CVE-2025-53628?: cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.20.1, cpp-httplib does not have a limit for a unique line, permitting an attacker to explore this to allocate memory arbitrarily. This vulnerability is fixed in 0.20.1. NOTE: This vulnerability is related to CVE-2025-53629.
How severe is CVE-2025-53628?: CVE-2025-53628 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2025-53628 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-53628?: CVE-2025-53628 affects Yhirose Cpp-httplib. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-53628?: 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.
Does CVE-2025-53628 have an EU (EUVD) identifier?: Yes. CVE-2025-53628 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-21053.
When was CVE-2025-53628 published?: CVE-2025-53628 was published on 2025-07-10 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:yhirose:cpp-httplib:*:*:*:*:*:*:*:*

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