Multiple stack-based buffer overflows in the pr_netio_telnet_gets function in netio.c in ProFTPD before 1.3.3c allow remote attackers to execute arbitrary code via vectors involving a TELNET IAC escape character to a (1) FTP or (2) FTPS server.
CVE-2010-4221
“—” beside the score: it is equal to NVD's CVSS v2 base score.
This CVE was only ever scored under CVSS v2.0. NVD CVSS v2.0 base 10.0 — NVD rates that HIGH (NVD's v2 bands: LOW 0.0–3.9 / MEDIUM 4.0–6.9 / HIGH 7.0–10.0; no CRITICAL band). Vector AV:N/AC:L/Au:N/C:C/I:C/A:C. CVSS v2 is an older, coarser metric than v3.1/v4.0 (no Scope, no User Interaction, no Attack Requirements), so it is not directly comparable to a v3 or v4 score. NVD has never re-scored this record under v3. EPSS predicts 91% exploitation probability in the next 30 days; it does not lift the v2 base. EPSS sets EG Risk's exploitation input. Confidence: LOW.
- High exploitation likelihood — EPSS 91%
- Public exploit code is available (Metasploit, Exploit-DB, marked verified by Exploit-DB, other public proof-of-concept code)
A fix is available — apply it.
- CVSS v2.0 (legacy)
- 10.0HIGHNVD never assigned a CVSS v3 rating to this CVE
- EG Score
- 10.0HIGHlow confidence
- EG Risk
- 82EG Risk 82/100
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computed (value × EchelonGraph’s weight)Severity100% × 45%The EG Score, 10.0 of 10.Exploitation91% × 40%FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.Automatability0% × 15%CISA's BOD 26-04 default: no one has published Automatable for this CVE, and CISA treats it as “no” for a CVE not in KEV.SSVC (CISA's decision table, applied by EchelonGraph): Track at low, Track* at medium and Attend at high mission impact.Exploitation public PoC (exploit code on record) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). EchelonGraph holds no SSVC assessment of this CVE from CISA: none of these inputs is from Vulnrichment. EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.Action: A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high. - EPSS PROB
- 91%
- EPSS %ILE
- 99th
- KEV
- Not listed
SSVC (CISA's decision table, applied by EchelonGraph)Track at low, Track* at medium and Attend at high mission impact.
A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
Exploitation public PoC (exploit code on record) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). EchelonGraph holds no SSVC assessment of this CVE from CISA: none of these inputs is from Vulnrichment. EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). Where an input reads “CISA's BOD 26-04 default”, no one has published it for this CVE, and CISA's implementation guidance says: “If “Automatable” and “Technical Impact” information items about a CVE ID are not available and the CVE ID is not in the KEV Catalog, CISA will treat its values as “no” and “total,” respectively, until CISA or a third party provides metadata about the CVE ID. CISA will always provide the Vulnrichment data for a CVE ID listed in the KEV Catalog.” Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it
Published
November 9, 2010
Last Modified
April 29, 2026
References (13)
- MITRE · CVE Programhttp://bugs.proftpd.org/show_bug.cgi?id=3521Exploit
- MITRE · CVE Programhttp://lists.fedoraproject.org/pipermail/package-announce/2010-November/050687.html
- MITRE · CVE Programhttp://lists.fedoraproject.org/pipermail/package-announce/2010-November/050703.html
- MITRE · CVE Programhttp://lists.fedoraproject.org/pipermail/package-announce/2010-November/050726.html
- MITRE · CVE Programhttp://secunia.com/advisories/42052 (archived copy: the site no longer serves it)Third-party advisory (tagged Vendor Advisory by NVD)
- MITRE · CVE Programhttp://secunia.com/advisories/42217 (archived copy: the site no longer serves it)
- MITRE · CVE Programhttp://www.mandriva.com/security/advisories?name=MDVSA-2010:227
- MITRE · CVE Programhttp://www.proftpd.org/docs/NEWS-1.3.3c
- MITRE · CVE Programhttp://www.securityfocus.com/bid/44562 (archived copy: the site no longer serves it)Exploit
- MITRE · CVE Programhttp://www.vupen.com/english/advisories/2010/2941
- MITRE · CVE Programhttp://www.vupen.com/english/advisories/2010/2959
- MITRE · CVE Programhttp://www.vupen.com/english/advisories/2010/2962
- MITRE · CVE Programhttp://www.zerodayinitiative.com/advisories/ZDI-10-229/
Affected Packages
(4 across 4 ecosystems)
Debian:11(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| proftpd-dfsg | — |
| — |
Debian:12(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| proftpd-dfsg | — |
| — |
Debian:13(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| proftpd-dfsg | — |
| — |
Debian:14(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| proftpd-dfsg | — |
| — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 3× in last 7d / 10× in last 30d)
Each row is a time one of our pipelines fetched, updated or re-scored this CVE. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.
A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. 13 repeat rows among the latest 90 are merged into the row they repeat.
- 2026-10-12 01:46 UTCEG score recompute
- 2026-10-09 20:00 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-10-08 16:33 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-10-03 14:20 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-10-01 02:40 UTCOSV refresh
- 2026-09-30 14:58 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-09-29 08:11 UTCEG score recompute
- 2026-09-24 13:57 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-09-20 20:08 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-09-12 14:54 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-09-12 05:53 UTCOSV refresh
- 2026-09-10 09:24 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-09-06 13:41 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-09-05 15:22 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-08-28 21:34 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-08-26 14:40 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-08-24 11:42 UTCOSV refresh
- 2026-08-19 16:58 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-08-18 13:42 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-08-16 02:09 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-08-08 07:49 UTCOSV refresh
- 2026-08-06 13:41 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-07-26 13:42 UTCEG score recomputeAssessed again: 10.0 HIGH
- 2026-07-23 01:06 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-07-23 01:05 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
Show 52 moreShow fewer
- 2026-07-23 01:04 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-07-23 01:03 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-07-23 01:02 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-07-23 01:01 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-07-23 01:01 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-07-23 00:59 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-07-23 00:58 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-07-23 00:57 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-07-23 00:56 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-07-23 00:55 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-07-23 00:54 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-07-23 00:53 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-07-23 00:52 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-07-23 00:51 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-07-23 00:50 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-07-23 00:49 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-07-23 00:48 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-07-23 00:47 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-07-23 00:45 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-07-23 00:44 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-07-23 00:43 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-07-23 00:43 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-07-23 00:42 UTCEG score recompute
- 2026-07-23 00:41 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-07-23 00:39 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-07-23 00:39 UTCEG score recompute▼ 9.00
- 2026-07-23 00:07 UTCEG score recompute
- 2026-07-22 21:46 UTCEG score recompute
- 2026-07-22 14:03 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-07-15 16:54 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-07-05 22:59 UTCOSV refresh
- 2026-06-30 23:19 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-06-29 14:02 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-06-28 04:52 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-06-24 14:02 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-06-23 21:29 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-06-17 17:49 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-06-17 10:05 UTCOSV refresh
- 2026-06-15 17:44 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-06-12 23:08 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-06-10 22:14 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-06-10 13:17 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-06-08 14:13 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-06-04 13:09 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-05-29 13:40 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-05-29 09:46 UTCEG score recompute
- 2026-05-29 09:46 UTCGHSA enrichmentGHSA-gf2w-q84f-pmmw · GitHub severity HIGH
- 2026-05-28 13:42 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-05-27 22:18 UTCOSV refresh
- 2026-05-21 22:39 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-05-20 22:37 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-05-18 21:29 UTCEPSS rescoreEPSS 92% · 99th percentile
Publicly available exploits
(6 references)Public exploit code is referenced for this CVE (2 Metasploit modules, 3 Exploit-DB entries, 1 GitHub PoC). Defenders should treat patch urgency accordingly.
- Exploit-DBEDB-16851✓ verifiedPublished Jan 9, 2011
ProFTPd 1.3.2 rc3 < 1.3.3b (Linux) - Telnet IAC Buffer Overflow (Metasploit)
Open source ↗ - Exploit-DBEDB-16878✓ verifiedPublished Dec 2, 2010
ProFTPd 1.3.2 rc3 < 1.3.3b (FreeBSD) - Telnet IAC Buffer Overflow (Metasploit)
Open source ↗ - Exploit-DBEDB-15449✓ verifiedPublished Nov 7, 2010
ProFTPd IAC 1.3.x - Remote Command Execution
Open source ↗ - Metasploitexploit/linux/ftp/proftp_telnet_iac✓ verifiedPublished Nov 5, 2010
ProFTPD 1.3.2rc3 - 1.3.3b Telnet IAC Buffer Overflow (Linux)
Open source ↗ - Metasploitexploit/freebsd/ftp/proftp_telnet_iac✓ verifiedPublished Nov 4, 2010
ProFTPD 1.3.2rc3 - 1.3.3b Telnet IAC Buffer Overflow (FreeBSD)
Open source ↗ - GitHub PoCM41doror/cve-2010-4221Published Oct 28, 2017
This exploit was written to study some concepts, enjoy!
Open source ↗
Related CVEs(same product + same CWE)
Same product
10 shownDebian:11:proftpd-dfsg
- CVE-2015-3306EG 10.0 KEVEPSS p100CRITICAL
- CVE-2006-5815EG 10.0EPSS p100HIGH
- CVE-2019-12815EG 9.8EPSS p99CRITICAL
- CVE-2023-48795NVD 5.9EG 9.0EPSS p100CRITICAL
- CVE-2011-4130EG 9.0EPSS p96HIGH
- CVE-2026-63090EG 8.8HIGH
- CVE-2020-9273EG 8.8EPSS p96HIGH
- CVE-2026-35025EG 8.1HIGH
- CVE-2026-44331EG 8.1HIGH
- CVE-2026-42167EG 8.1EPSS p94HIGH
Same CWE
10 shownCWE-119
- CVE-2010-4216EG 5.0MEDIUM
- CVE-2010-3333NVD 7.8EG 9.0 KEVEPSS p100CRITICAL
- CVE-2010-3334EG 9.3EPSS p98HIGH
- CVE-2010-3335EG 9.3EPSS p98HIGH
- CVE-2010-3336EG 9.3EPSS p98HIGH
- CVE-2010-4091EG 9.3EPSS p97HIGH
- CVE-2010-3637EG 9.3EPSS p93HIGH
- CVE-2010-3894EG 9.3EPSS p96HIGH
- CVE-2010-3846EG 6.9MEDIUM
- CVE-2010-3785EG 6.8MEDIUM
Frequently asked(4)
What is CVE-2010-4221?
When was CVE-2010-4221 made public?
Is CVE-2010-4221 actively exploited?
How do I remediate CVE-2010-4221?
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2010-4221
Is Your Infrastructure Affected by CVE-2010-4221?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.