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CVE-2001-0751· NVD / CVE Program· CNA mitre

Cisco switches and routers running CBOS 2.3.8 and earlier use predictable TCP Initial Sequence Numbers (ISN), which allows remote attackers

Cisco switches and routers running CBOS 2.3.8 and earlier use predictable TCP Initial Sequence Numbers (ISN), which allows remote attackers to spoof or hijack TCP connections.

HighCVSS 7.5 · v2.0—Proof of concept No fix recorded
Published
Oct 18, 2001
Updated
Jun 16, 2026
EPSS
2.6% · 85th percentile
CWE
—
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Report tools

JSON

Action score

31

Monitor

Low priority for now.

CVSS
30 / 40 · 7.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
1 / 30 · 2.6%

Affected systems

VendorProduct
ciscocbos

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • cisco cbosup to 2.3.8 inclusive

Same product

cisco: all records

Other highest-scoring records for the same primary product.

  • CVE-2001-0753Cisco CBOS 2.3.8 and earlier stores the passwords for (1) exec and (2) enable in cleartext in the NVRAM and a configuration file, which coul
    30Monitor
  • CVE-2002-0886Cisco DSL CPE devices running CBOS 2.4.4 and earlier allows remote attackers to cause a denial of service (hang or memory consumption) via (
    22Monitor
  • CVE-2001-1064Cisco 600 series routers running CBOS 2.0.1 through 2.4.2ap allows remote attackers to cause a denial of service via multiple connections to
    22Monitor
  • CVE-2001-0754Cisco CBOS 2.3.8 and earlier allows remote attackers to cause a denial of service via a series of large ICMP ECHO REPLY (ping) packets, whic
    20Monitor
  • CVE-2001-0752Cisco CBOS 2.3.8 and earlier allows remote attackers to cause a denial of service via an ICMP ECHO REQUEST (ping) with the IP Record Route o
    20Monitor
  • CVE-2001-1065Web-based configuration utility in Cisco 600 series routers running CBOS 2.0.1 through 2.4.2ap binds itself to port 80 even when web-based c
    20Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

No fix version is recorded for this entry. Check the references for vendor advisories.

Exploit status

Proof of concept available

A public proof of concept or detection signature exists. Exploit knowledge is out there; don't delay patching.

Evidence

  • Exploit-DB entry ×1

Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.

Public exploit evidence
SourceKindDate
Exploit-DB entryremote1999-09-27

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

  1. First PoC-752 d
  2. Published
  3. TodaySep 30, 2026+9114 d
EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • No special conditions are required; it is repeatable.

If successful

Confidentiality
P · data can be read
Integrity
P · data or configuration can be modified
Availability
P · the service can be disrupted
Attack complexity
Low
Confidentiality impact
P
Integrity impact
P
Availability impact
P

Weakness class (CWE)

—

CVSS vector

AV:N/AC:L/Au:N/C:P/I:P/A:P

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Noroxi analysis

No Noroxi analysis for this record yet

We don't hand-write analysis for all 385,000+ vulnerabilities; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.

We use this product, ask for help

Change log

No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.

References

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records