Reference page — cumulative record through Monday, October 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
CVE-2021-22898
n/a https://github.com/curl/curl — curl 7.7 through 7.76.1 suffers from an information disclosure when the `-t` command line option, known as `CURLOPT_TELNETOPTIONS` in lib…
AV AC PR UI S C I A CVSS EPSS %ile KEV
N H N R U L N N 3.1 .0451 91.4 —
AFFECTED
Product Versions Fixed
https://github.com/curl/curl 7.7 through 7.76.1 – —
TIMELINE
Jan 6 Reserved by hackerone
Jun 11 Published (CNA: hackerone)
Oct 14 EXPLOIT PUBLISHED — CVE-2021-22898 (https://github.com/curl/curl). Public exploit reference added.
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. Due to a flaw in the option parser for sending NEW_ENV variables, libcurl could be made to pass on uninitialized data from a stack based buffer to the server, resulting in potentially revealing sensitive internal information to the server using a clear-text network protocol.
Lifecycle
Complete event history — 3 events, chronological
| Date | Event | Detail |
|---|
| January 6, 2021 | Reserved | Reserved by hackerone |
| June 11, 2021 | Published | Published (CNA: hackerone) |
| October 14, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2021-22898 (https://github.com/curl/curl). Public exploit reference added. |
Affected
Affected products and packages — 1 row
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
|---|
| n/a | https://github.com/curl/curl | — | 7.7 through 7.76.1 | — |
References (15)
- http://www.openwall.com/lists/oss-security/2021/07/21/4 [Mailing List, Patch, Third Party Advisory]
- https://cert-portal.siemens.com/productcert/html/ssa-398330.html
- https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf [Patch, Third Party Advisory]
- https://curl.se/docs/CVE-2021-22898.html [Exploit, Patch, Vendor Advisory]
- https://github.com/curl/curl/commit/39ce47f219b09c380b81f89fe54ac586c8db6bde [Patch, Third Party Advisory]
- https://hackerone.com/reports/1176461 [Exploit, Issue Tracking, Patch, Third Party Advisory]
- https://lists.apache.org/thread.html/rc713534b10f9daeee2e0990239fa407e2118e4aa9e88a7041177497c%40%3Cissues.guacamole.apache.org%3E [Mailing List, Third Party Advisory]
- https://lists.debian.org/debian-lts-announce/2021/08/msg00017.html [Mailing List, Third Party Advisory]
- https://lists.debian.org/debian-lts-announce/2022/08/msg00017.html [Third Party Advisory]
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FRUCW2UVNYUDZF72DQLFQR4PJEC6CF7V/ [Mailing List, Third Party Advisory]
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/POOC3UV7V6L4CJ5KA2PTWTNUV5Y72T3Q/ [Mailing List, Third Party Advisory]
- https://www.debian.org/security/2022/dsa-5197 [Third Party Advisory]
- https://www.oracle.com//security-alerts/cpujul2021.html [Patch, Third Party Advisory]
- https://www.oracle.com/security-alerts/cpuapr2022.html [Patch, Third Party Advisory]
- https://www.oracle.com/security-alerts/cpujan2022.html [Patch, Third Party Advisory]
About this page
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2021-22898 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Monday, October 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.
