How severe is CVE-2022-37797?

CVE-2022-37797 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-2022-37797 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2022-37797?

CVE-2022-37797 primarily affects Lighttpd. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2022-37797?

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-2022-37797 published?

CVE-2022-37797 was published on 2022-09-12 and last updated on 2026-06-17.

CVE-2022-37797

CVE-2022-37797 is a high-severity vulnerability in Lighttpd 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-476.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 2% (78th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-476
Affected product: Lighttpd
Published: 2022-09-12
Last modified: 2026-06-17

Description

In lighttpd 1.4.65, mod_wstunnel does not initialize a handler function pointer if an invalid HTTP request (websocket handshake) is received. It leads to null pointer dereference which crashes the server. It could be used by an external attacker to cause denial of service condition.

Frequently asked questions

What is CVE-2022-37797?: In lighttpd 1.4.65, mod_wstunnel does not initialize a handler function pointer if an invalid HTTP request (websocket handshake) is received. It leads to null pointer dereference which crashes the server. It could be used by an external attacker to cause denial of service condition.
How severe is CVE-2022-37797?: CVE-2022-37797 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-2022-37797 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-37797?: CVE-2022-37797 primarily affects Lighttpd. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2022-37797?: 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-2022-37797 published?: CVE-2022-37797 was published on 2022-09-12 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:lighttpd:lighttpd:1.4.65:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*

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