Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff51799c104243ef…

MALICIOUS

PDF

75.8 KB Created: 2021-03-31 09:43:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 288f61e310d78e48afcbef57a63d39b2 SHA-1: c36d77d466a8ec5b0f5f8cea3da0a77ba563b6a0 SHA-256: ff51799c104243efa5c2369beb4ad24314e716f04f8f6c431d0498cb65bb6650
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of a link farm. It contains numerous external links, many pointing to disposable hosting services, suggesting an attempt to redirect users to potentially harmful content. The document body, though heavily obfuscated, appears to be a lure related to educational materials, aligning with phishing or scam tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://jottigo.ru/award?keyword=cbse+class+11+maths+book+pdf+download PDF link annotation
    • https://kekorozonositen.weebly.com/uploads/1/3/2/7/132710750/nagavekog_fududemu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4405904/normal_605650a964473.pdfIn PDF document text
    • https://gedotelebuguda.weebly.com/uploads/1/3/6/0/136050260/4d62c397.pdfIn PDF document text
    • https://cdn.sqhk.co/pewowutefiw/e5Yidg5/tekewose.pdfIn PDF document text
    • https://cdn.sqhk.co/sewadokoka/ligdDcC/tom_runnels_mlb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4405644/normal_6056b093ad399.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367668/normal_603f3179107bc.pdfIn PDF document text
    • https://cdn.sqhk.co/gasosivifug/BYidrgc/ps4_simulation_games_2018.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379973/normal_604d0f37585de.pdfIn PDF document text
    • https://cdn.sqhk.co/rolekixawute/mJzJjer/free_antivirus_smadav_pc.pdfIn PDF document text
    • https://bemofoserobonuw.weebly.com/uploads/1/3/0/7/130739893/9423724.pdfIn PDF document text
    • https://fanolukexepafo.weebly.com/uploads/1/3/0/9/130969893/5226909.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4444622/normal_605a92f6b37b5.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4392199/normal_6003cda9e2b7b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4419828/normal_6017feb309366.pdfIn PDF document text
    • https://kofovozeregom.weebly.com/uploads/1/3/4/3/134313602/kakevizobibolep.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/622a6940-a850-460c-9521-9d2f6dce9d3e/lds_nursery_birthday_ideas.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f79780d9-0125-4a84-a845-81b2a13e6b4b/50160569195.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e205dc0e-8340-4560-b190-a728941299d5/what_does_it_mean_when_your_car_says_ice_possible.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e4f8755b-738b-4840-820c-dcdca1bd36f7/windows_7_secrets_and_hacks.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/19c1c062-f336-414e-a421-ca2a29f8648b/adt_safewatch_pro_3000_installation_manual.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e90a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE90A 5552 bytes
SHA-256: f29e1c39275369573f83a914506665f3eb509c3b0cd3244dcb3f04bc978d5e76
font_01_sfnt_off0000fbd9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBD9 11188 bytes
SHA-256: 318b7d955b5f9e9b226c924d529a238ccd92de8344f6335f8855f79f0c172fc9