How severe is CVE-2020-27853?

CVE-2020-27853 has a CVSS 3.x base score of 9.8, 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 high.

Is CVE-2020-27853 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-27853?

CVE-2020-27853 primarily affects Wire. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-27853?

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-2020-27853 published?

CVE-2020-27853 was published on 2020-10-27 and last updated on 2026-06-17.

CVE-2020-27853

CVE-2020-27853 is a critical-severity vulnerability in Wire with a CVSS 3.x base score of 9.8. 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-134.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 4% (89th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-134
Affected product: Wire
Published: 2020-10-27
Last modified: 2026-06-17

Description

Wire before 2020-10-16 allows remote attackers to cause a denial of service (application crash) or possibly execute arbitrary code via a format string. This affects Wire AVS (Audio, Video, and Signaling) 5.3 through 6.x before 6.4, the Wire Secure Messenger application before 3.49.918 for Android, and the Wire Secure Messenger application before 3.61 for iOS. This occurs via the value parameter to sdp_media_set_lattr in peerflow/sdp.c.

Frequently asked questions

What is CVE-2020-27853?: Wire before 2020-10-16 allows remote attackers to cause a denial of service (application crash) or possibly execute arbitrary code via a format string. This affects Wire AVS (Audio, Video, and Signaling) 5.3 through 6.x before 6.4, the Wire Secure Messenger application before 3.49.918 for Android, and the Wire Secure Messenger application before 3.61 for iOS. This occurs via the value parameter to sdp_media_set_lattr in peerflow/sdp.c.
How severe is CVE-2020-27853?: CVE-2020-27853 has a CVSS 3.x base score of 9.8, 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 high.
Is CVE-2020-27853 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-27853?: CVE-2020-27853 primarily affects Wire. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-27853?: 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-2020-27853 published?: CVE-2020-27853 was published on 2020-10-27 and last updated on 2026-06-17.

References

Affected products (6)

cpe:2.3:a:wire:wire:*:*:*:*:*:linux:*:*
cpe:2.3:a:wire:wire:*:*:*:*:*:windows:*:*
cpe:2.3:a:wire:wire:*:*:*:*:*:macos:*:*
cpe:2.3:a:wire:wire_-_audio\,_video\,_and_signaling:*:*:*:*:*:*:*:*
cpe:2.3:a:wire:wire_secure_messenger:*:*:*:*:*:android:*:*
cpe:2.3:a:wire:wire_secure_messenger:*:*:*:*:*:iphone_os:*:*

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Other CWE-134 vulnerabilities

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CVE-2011-2475 — Critical (CVSS 10.0): Format string vulnerability in ECTrace.dll in the iMailGateway service in the Internet Mail Gateway in OneBridge Server…
CVE-2011-1568 — Critical (CVSS 10.0): Format string vulnerability in the logText function in shmemmgr9.dll in IGSSdataServer.exe 9.00.00.11074, and…
CVE-2010-4235 — Critical (CVSS 10.0): Format string vulnerability in RealNetworks Helix Server 12.x, 13.x, and 14.x before 14.2, and Helix Mobile Server…
CVE-2011-0270 — Critical (CVSS 10.0): Format string vulnerability in nnmRptConfig.exe in HP OpenView Network Node Manager (OV NNM) 7.51 and 7.53 allows…

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