CVE-2021-22898
curl 7.7 through 7.76.1 suffers from an information disclosure when the `-t` command line option, known as `CURLOPT_TELNETOPTIONS` in libcurl, is used to send variable=content pairs to TELNET servers.
02 Description
curl 7.7 through 7.76.1 suffers from an information disclosure when the `-t` command line option, known as `CURLOPT_TELNETOPTIONS` in libcurl, is used to send variable=content pairs to TELNET servers.
03 Exploitation and scoring
- Exploitation
- Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.
- SSVC decision
- ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
- AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
- Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.
- EPSS probability
- 4.50% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 91.4% of scored records. A rank, not a probability.
- NVD base score
- 3.1 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N
- NVD analysis status
- Modified. NVD last modified this record on 2026-10-14.
- Red Hat severity
- Low. Red Hat's rating for its own products, not a CVSS rating.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2021-06-11 15:49Z5 YR AGO
- Last updated
- 2026-10-14 10:21Z15 DAYS AGO
- Reserved
- 2021-01-06
- Assigning CNA
- hackerone
- Record state
- PUBLISHED
- Severity
- Low (CVSS 3.1)
- CNA CVSS vector
- CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N
- Weaknesses
- Data version
- 5.2
- Document digest
- b3eb962b40074c4064de1bfcf5cb05fb7e0bc8806267418b17a56df9b424cb02
05 Affected products
06 References
- hackerone.comhttps://hackerone.com/reports/1176461
- curl.sehttps://curl.se/docs/CVE-2021-22898.html
- github.comhttps://github.com/curl/curl/commit/39ce47f219b09c380b81f89fe54ac586c8db6bde
- lists.apache.org[guacamole-issues] 20210618 [jira] [Created] (GUACAMOLE-1368) Latest docker image fails security scans.https://lists.apache.org/thread.html/rc713534b10f9daeee2e0990239fa407e2118e4aa9e88a7041177497c%40%3Cissues.guacamole.apache.org%3E
- www.oracle.comhttps://www.oracle.com//security-alerts/cpujul2021.html
- www.openwall.com[oss-security] 20210721 [SECURITY ADVISORY] curl: TELNET stack contents disclosure againhttp://www.openwall.com/lists/oss-security/2021/07/21/4
- lists.fedoraproject.orgFEDORA-2021-83fdddca0fhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/POOC3UV7V6L4CJ5KA2PTWTNUV5Y72T3Q/
- lists.fedoraproject.orgFEDORA-2021-5d21b90a30https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FRUCW2UVNYUDZF72DQLFQR4PJEC6CF7V/
- lists.debian.org[debian-lts-announce] 20210813 [SECURITY] [DLA 2734-1] curl security updatehttps://lists.debian.org/debian-lts-announce/2021/08/msg00017.html
- www.oracle.comhttps://www.oracle.com/security-alerts/cpujan2022.html
- www.oracle.comhttps://www.oracle.com/security-alerts/cpuapr2022.html
- cert-portal.siemens.comhttps://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf
- www.debian.orgDSA-5197https://www.debian.org/security/2022/dsa-5197
- lists.debian.org[debian-lts-announce] 20220828 [SECURITY] [DLA 3085-1] curl security updatehttps://lists.debian.org/debian-lts-announce/2022/08/msg00017.html
- cert-portal.siemens.comhttps://cert-portal.siemens.com/productcert/html/ssa-398330.html
07 Fixed in
AlmaLinux 8
- curl Fixed in 7.61.1-22.el8
- libcurl Fixed in 7.61.1-22.el8
- libcurl-devel Fixed in 7.61.1-22.el8
- libcurl-minimal Fixed in 7.61.1-22.el8
Source: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.
Arch Linux
- curl Fixed in 7.77.0-1
- lib32-curl Fixed in 7.77.0-1
- lib32-libcurl-compat Fixed in 7.77.0-1
- lib32-libcurl-gnutls Fixed in 7.77.0-1
- libcurl-compat Fixed in 7.77.0-1
- libcurl-gnutls Fixed in 7.77.0-1
Source: Arch Linux Security Tracker, the Arch Linux security team. Reformatted by exploit.cc.
CloudLinux 8
- curl Fixed in 7.61.1-22.el8
- libcurl Fixed in 7.61.1-22.el8
- libcurl-devel Fixed in 7.61.1-22.el8
- libcurl-minimal Fixed in 7.61.1-22.el8
Derived from AlmaLinux 8. Partial coverage: only packages taken from AlmaLinux 8 are listed.
Source: CloudLinux errata, CloudLinux Inc. Derived from: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.
Debian 12
- curl Fixed in 7.79.1-1
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 13
- curl Fixed in 7.79.1-1
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 14
- curl Fixed in 7.79.1-1
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 18.04 LTS
- curl Fixed in 7.58.0-2ubuntu3.14
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 20.04 LTS
- curl Fixed in 7.68.0-1ubuntu2.6
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro 14.04 LTS
- curl Fixed in 7.35.0-1ubuntu2.20+esm14Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro 16.04 LTS
- curl Fixed in 7.47.0-1ubuntu2.19+esm3Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
A release or ecosystem missing from this list has no record here. It may be unaffected or not covered by the source. Source notices and licences.