How severe is CVE-2018-21245?

CVE-2018-21245 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2018-21245 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-21245?

CVE-2018-21245 affects Apsis Pound. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-21245?

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

When was CVE-2018-21245 published?

CVE-2018-21245 was published on 2020-06-15 and last updated on 2026-06-17.

CVE-2018-21245

CVE-2018-21245 is a critical-severity vulnerability in Apsis Pound with a CVSS 3.x base score of 9.1. 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: Critical (CVSS 3.x base score 9.1)
CVSS v2: 6.4
EPSS exploit prediction: 1% (62nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-444
Affected product: Apsis Pound
Published: 2020-06-15
Last modified: 2026-06-17

Description

Pound before 2.8 allows HTTP request smuggling, a related issue to CVE-2016-10711.

Frequently asked questions

What is CVE-2018-21245?: Pound before 2.8 allows HTTP request smuggling, a related issue to CVE-2016-10711.
How severe is CVE-2018-21245?: CVE-2018-21245 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2018-21245 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-21245?: CVE-2018-21245 affects Apsis Pound. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-21245?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2018-21245 published?: CVE-2018-21245 was published on 2020-06-15 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:apsis:pound:*:*:*:*:*:*:*:*

More vulnerabilities in Apsis Pound

CVE-2016-10711 — Critical (CVSS 9.8): Apsis Pound before 2.8a allows request smuggling via crafted headers, a different vulnerability than CVE-2005-3751.
CVE-2005-1391 — High (CVSS 7.5): Buffer overflow in the add_port function in APSIS Pound 1.8.2 and earlier allows remote attackers to execute arbitrary…
CVE-2004-2026 — High (CVSS 7.5): Format string vulnerability in the logmsg function in svc.c for Pound 1.5 and earlier allows remote attackers to…
CVE-2005-3751 — Medium (CVSS 4.3): HTTP request smuggling vulnerability in Pound before 1.9.4 allows remote attackers to poison web caches, bypass web…

All CVEs affecting Apsis Pound →

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