CVE-2021-31810
mediumpriority · track · 24EPSS 0.030 · 87 %ileDEEURUUSEPSS · scored 2026-10-27
An issue was discovered in Ruby through 2.6.7, 2.7.x through 2.7.3, and 3.x through 3.0.1. A malicious FTP server can use the PASV response to trick Net::FTP into connecting back to a given IP address and port. This potentially makes curl extract information about services that are otherwise private and not disclosed (e.g., the attacker can conduct port scans and service banner extractions).
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (43)
Products and version ranges known to be affected.
advisories (3)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2022-1305Ruby: Mehrere SchwachstellenDeutsch2021-07-07csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Ruby ausnutzen, um Sicherheitsvorkehrungen zu umgehen und vertrauliche Informationen offenzulegen.
- BIT-ruby-2021-318102024-03-06vendor · osvUS
An issue was discovered in Ruby through 2.6.7, 2.7.x through 2.7.3, and 3.x through 3.0.1. A malicious FTP server can use the PASV response to trick Net::FTP into connecting back to a given IP address and port. This potentially makes curl extract information about services that are otherwise private and not disclosed (e.g., the attacker can conduct port scans and service banner extractions).
- BIT-ruby-min-2021-318102025-01-27vendor · osvUS
An issue was discovered in Ruby through 2.6.7, 2.7.x through 2.7.3, and 3.x through 3.0.1. A malicious FTP server can use the PASV response to trick Net::FTP into connecting back to a given IP address and port. This potentially makes curl extract information about services that are otherwise private and not disclosed (e.g., the attacker can conduct port scans and service banner extractions).
also known as (6)
Other names and identifiers for this entity.
- CNNVD-202107-409cnnvd
- EUVD-2021-18688enisa_euvd
- BDU:2021-04565fstec_bdu
- GHSA-wr95-679j-87v9enisa_euvd
- BIT-ruby-2021-31810osv
- BIT-ruby-min-2021-31810osv
sources
Which sources assert this record, and when.
references (53)
External citations — patches, advisories, analysis.
- https://access.redhat.com/security/cve/cve-2021-31810cnnvd
- https://hackerone.com/reports/1145454cnnvd
- https://lists.debian.org/debian-lts-announce/2021/10/msg00009.htmlcnnvd
- https://lists.debian.org/debian-lts-announce/2023/04/msg00033.htmlcnnvd
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/MWXHK5UUHVSHF7HTHMX6JY3WXDVNIHSL/cnnvd
- https://packetstormsecurity.com/files/163622/Ubuntu-Security-Notice-USN-5020-1.htmlcnnvd
- https://packetstormsecurity.com/files/163745/Red-Hat-Security-Advisory-2021-3020-01.htmlcnnvd
- https://packetstormsecurity.com/files/164211/Red-Hat-Security-Advisory-2021-3559-01.htmlcnnvd
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