Cisco IP Phone 7821 (7821)

Cisco IP Phone 7821 (7821)
Security Grade C Calculator v1	Cisco IP Phone 7821 Brand: Cisco (Parent: Cisco Systems, Inc.) Category: VoIP desk phone • Model / Gen: 7800 Series (7821; no numbered generation specified). 7821 Release Date: 2013-11-08 • Status: In sale Classification Date: 2026-10-24 • Official Website

Security Evaluation

1. Device Security

Criterion	Value	Proof	Comment
Known hardware tampering	Rare	🔗 Proof	Researchers physically removed and read flash memory to recover the phone's administrative password; hardware access therefore exposes a practical confidentiality weakness.
Known vulnerabilities	Rare	🔗 Proof	The exact tested firmware stores the administrative phone password insecurely; Cisco fixed CVE-2022-20660 in 14.1(1). Additional primary evidence: source 2.
Prior attacks	None	🔗 Proof	Cisco PSIRT reported no known malicious use of this vulnerability at publication. No exact7821 field campaign was established in this bounded primary-source review. Evidence boundary: This does not assert that no real attack ever occurred; the physical proof of concept is not a botnet/campaign event.
Updatability	Very common	🔗 Proof	Cisco documents the12.8 firmware installation workflow and released14.1(1) to fix the disclosed flash issue; its model support history includes multiple maintained firmware branches. Score1 is a qualitative maintenance judgment. Evidence boundary: Historical maintained-firmware availability, not a numerical update cadence or a claim that this old installed image is current. Later lifecycle status is separate. Additional primary evidence: source 2; source 3.
Category Score	Score: 2 / 3

2. System Security

Criterion	Value	Proof	Comment
Authentication with other systems	Partial	🔗 Proof	Signed provisioning files and trusted service verification authenticate part of the Enterprise infrastructure. The selected nonsecure call profile does not provide comprehensive authenticated protection for every peer. Evidence boundary: Do not equate Security by Default with default media encryption or a universally mutually authenticated network.
Communications	No encryption	🔗 Proof	The explicitly selected nonsecure call profile does not provide encrypted media; encrypted signaling and media require a separately configured secure profile. Evidence boundary: SEC Consult demonstrated cleartext data in a raw flash dump after TFTP XML provisioning, not a packet-capture result proving unencrypted network credentials. No default HTTP management claim is made; web access is normally disabled. Additional primary evidence: source 2.
Storage	No encryption	🔗 Proof	A raw flash-chip dump revealed the administrative password in plaintext at multiple locations in the exact tested phone. Additional primary evidence: source 2.
Category Score	Score: 3 / 3

3. User Authentication

Criterion	Value	Proof	Comment
Account management	Basic	🔗 Proof	Local settings use a device unlock password; personal user identities and group administration reside in the external CUCM system. Evidence boundary: The external server has richer user management. Basic here describes phone-local administrative identity controls rather than denying those central features.
Authentication	Basic	🔗 Proof	Administrative options can require the provisioned phone password, but the tested flash exposure permits physical recovery of that secret. Evidence boundary: Ordinary call use is not a personal authentication requirement. No MPP first-login behavior is imported. Additional primary evidence: source 2.
Brute-force protection	Basic	🔗 Proof	Configured CUCM credential policies lock out repeated Extension Mobility PIN failures; protection of the separate local unlock password is not established. Evidence boundary: Server dependency and administrator configuration are required. This does not claim an enabled factory-default or comprehensive local rate limit. Additional primary evidence: source 2.
Event logging	Partial logging	🔗 Proof	The phone manual documents status and diagnostic logs. These support partial monitoring, without proving a complete user or administrator access audit. Evidence boundary: Debug logs and call statistics must not be described as complete security auditing.
Passwords	Require change after setup	🔗 Proof	This literature deployment explicitly provisions a unique local Phone Password for this handset at installation. Score2 follows the Methodology's unique-credential intent; it does not assert a factory-enforced post-setup password rotation rule. Evidence boundary: Installation uniqueness is an explicit deployment condition, not an inspected real handset or an inherent factory guarantee. The researcher's sectest password is not a default. CUCM PIN policies are not misrepresented as local unlock-password enforcement. Additional primary evidence: source 2.
Category Score	Score: 2 / 3

Technical Specifications

Property	Details
Operating System & App	Cisco Enterprise SIP firmware 12.8.1-0001-455 (assessed version). (Companion App: Cisco Unified CM Self Care Portal (deployment-side web configuration; no dedicated companion mobile app specified).)
Hardware (CPU / GPU)	CPU: Not publicly disclosed in cited manufacturer documentation. • GPU: Not publicly disclosed in cited manufacturer documentation.
Memory & Storage	Memory: Not publicly disclosed in cited manufacturer documentation. • Storage: Internal flash; capacity not publicly disclosed in cited manufacturer documentation.
Power, Battery & Charging	Battery: Not applicable for normal operation: powered by PoE or external DC supply. • Power: IEEE 802.3af PoE Class 1, or external 48 V DC supply. • Charging: Not applicable: desk phone uses PoE/external power rather than a charging workflow.
Display & Camera	Display: 3.5-inch, 396 x 162-pixel greyscale display with white backlight. • Camera: Not applicable: audio desk phone; no integrated camera specified.
Sound & Connectivity	Sound: Wideband handset; full-duplex speakerphone; RJ-9 analog headset port. • Connectivity: Two RJ-45 10/100BASE-T ports (LAN and PC); RJ-9 handset/headset connections.
Physical (Dimensions & Mass)	Dimensions: 207 x 206 x 28 mm (H x W x D; excluding foot stand). • Mass: 867 g.

Assessment scope

Documentation-based historical Enterprise deployment: Cisco 7821, firmware 12.8.1-0001-455 exactly tested by SEC Consult in 2021 and disclosed 13 January 2022. Define CUCM 12.5(1)SU3, a nonsecure call profile, a unique administrator-provisioned Phone Password for this phone, and Extension Mobility PINs governed by configured CUCM lockout. These deployment choices are documented capabilities, not SEC Consult's complete observed setup or factory defaults. Local phone and central CUCM credentials are assessed as separate boundaries. No physical installation or test was performed by the author.

Method and evidence boundaries

This is a documentary case-study assessment of the exact hardware, firmware and explicitly stated configuration, reviewed on 24 October 2026. No physical installation, penetration test or traffic capture by the author is claimed. Historical flaws do not establish current unpatched exposure. The website supplies qualitative categories rather than statistical thresholds: repeated real maintenance supports Updatability 1; isolated/uncertain maintenance supports2; a documented no-update condition supports3. Vulnerability/attack frequency labels are reasoned judgments, and a laboratory demonstration is not an observed campaign. None for prior attacks means no exact-model field campaign established in the reviewed sources, not proof of lifetime absence. Communications follows the least-protected enabled path carrying control, credentials or application payloads; a DNS/discovery packet alone is not used to label an entire device unencrypted. Storage evaluates confidential device-resident flash contents, not merely cloud security or whether executable firmware is readable. For Passwords, the methodology discusses first-setup credentials and expressly allows unique initial passwords. Where mandatory first-use creation or explicitly configured unique credentials do not match a shared-default-change label literally, option2 is a disclosed functional mapping, not a claim of forced periodic rotation. Option1 additionally requires enforced complexity; option3 requires positive evidence of common, predictable or unprotected access. Dates preserve the identified manufacturer announcement/availability or clearly identified primary regional catalog basis. No arbitrary first-of-month date is inserted. The calculated IDRS device grade is not a manufacturer certification or a student assignment mark.

Calculated IDRS: 2 + 3 + 2 = 7 (C).

Date basis: Cisco France's dated 8 November 2013 product announcement explicitly names 7821 and states the three new phones are available today. This record uses that regional official announcement/availability day, not a claimed worldwide first-sale day; the separate series support page lists 22 October 2013. Date source: https://gblogs.cisco.com/fr/collaboration/cisco-devoile-la-gamme-de-telephones-cisco-ip-phone-7800/

Product-specific boundaries: This is an Enterprise CUCM literature configuration; MPP defaults and manuals do not apply. The physical flash finding was repaired in later firmware; the grade is for the specified historical image. The installation-unique phone password and CUCM lockout are explicit assessment conditions, not claimed factory defaults or SEC Consult's complete test setup. Password2 is the disclosed unique-credential operational interpretation of the site prose; its dropdown label is not presented as literal enforced password rotation. The official8 November 2013 France announcement supplies an exact, clearly scoped availability/announcement date.

Hardware and general-information supplement

Supplement reviewed on 25 October 2026. Manufacturer model specifications and explicitly identified historical manuals support the added fields. Hardware capabilities do not imply that optional services, accessories or every capacity variant are enabled in the assessed case. Unpublished or unverified parameters are identified rather than guessed. Current sale/support status is separate from the original historical firmware/configuration assessment; the twelve security selections and original evidence have not been changed.

Specification evidence

• Generation, Dimensions, Mass, CPU, GPU, Memory, Display, Sound: source 1.
• Status: source 1.
• Operating system: source 1.
• Companion App: source 1.
• Storage: source 1; source 2.
• Battery, Charging: source 1.
• Power, Camera, Connectivity: source 1; source 2.

Specification qualifications

• The assessed firmware is Enterprise SIP 12.8.1-0001-455, rather than Multiplatform Phone firmware.
• Unpublished processor and memory-capacity details are treated as unknown, not as absent hardware.
• Current In sale status is bounded by the official last-order date 28 October 2026; last support is 31 October 2031. Announcement of lifecycle milestones is not already-completed end of support.