Malicious PDF — malware analysis report

Static analysis result for SHA-256 a171ed454de450e9…

MALICIOUS

PDF

81.8 KB Created: 2021-04-25 23:27:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 58b5e7795d39c9f190d70dea74e8e0c7 SHA-1: 548f46f9d3a51656df86682298f61a486e4d6624 SHA-256: a171ed454de450e9cfee43a4f8951256f69da2c50d3c78c9e74347c0ebfcf0bf
186 Risk Score

Malware Insights

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

The PDF file contains a link farm designed to redirect users to potentially malicious content, masquerading as a printer driver download. The heuristic PDF_SEO_LINK_FARM indicates a mass of external links, with one pointing to `https://soxebez.ru/strik?utm_term=hp+laserjet+1100+printer+driver+for+windows+10+64+bit`. While no scripts were explicitly extracted, the nature of the link farm and the ML classifier's high confidence suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://soxebez.ru/strik?utm_term=hp+laserjet+1100+printer+driver+for+windows+10+64+bit PDF link annotation
    • https://cdn.sqhk.co/sirepajaku/qeVGjgt/30824289071.pdfIn PDF document text
    • https://cdn.sqhk.co/powirafawume/Bhb3ngd/27259220452.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4402710/normal_600383b88b239.pdfIn PDF document text
    • https://cdn.sqhk.co/julubesaf/jhOWiim/57495307728.pdfIn PDF document text
    • http://ca-manalapan.space/sad_songs_tonesucgq8.pdfIn PDF document text
    • http://dkblogin-de.com/casio_hr-8tm_manual_en_espaol2zpew.pdfIn PDF document text
    • https://cdn.sqhk.co/xekemini/aAjgggY/zoxiripaxabenijotopanaj.pdfIn PDF document text
    • https://cdn.sqhk.co/puviponapib/jage9hb/scientist_resume_template_word.pdfIn PDF document text
    • https://cdn.sqhk.co/rajunakeb/nxhfggq/26270263807.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374986/normal_6036371f3a6c0.pdfIn PDF document text
    • https://cdn.sqhk.co/doporaba/ic6BXgc/kinamuwobafegotilukiwege.pdfIn PDF document text
    • https://cdn.sqhk.co/pijovowifil/2hhhWih/songs_like_on_my_own_les_miserables.pdfIn PDF document text
    • https://cdn.sqhk.co/wevemugas/cIRVF4h/slacker_definition_and_sentence.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/savifin/wefujavo.pdfIn PDF document text
    • https://s3.amazonaws.com/nafoxuda/10760156242.pdfIn PDF document text
    • https://8e0cabef-d481-4215-b437-8a5fc4e4723c.filesusr.com/ugd/f41140_9e1c7f37c71242c98b3fa8399a024206.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/boduxatavepe/61478049058.pdfIn PDF document text
    • https://bbaef297-c986-4b42-acb3-0fd65605e280.filesusr.com/ugd/e9fc71_72e6363479b949408d101e0ed2f2c2a2.pdf?index=trueIn PDF document text
    • https://5c839259-519f-4cee-a1a2-6639d654070b.filesusr.com/ugd/140efa_3b667deebd0640f6bada960edfc97075.pdf?index=trueIn PDF document text
    • https://318abaa7-a496-4882-a5ef-186b1d719b20.filesusr.com/ugd/ff2e65_ee06f311a1d0477c8d2936f2fb838055.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/jasadavebaga/mukediripudezowunow.pdfIn PDF document text
    • https://0e75ab8e-f6a1-4360-bef2-1d94e06fde4e.filesusr.com/ugd/c0518c_6d2c700241ef4ce6a8202cd6f863f98b.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/vifusupegiza/finite_element_analysis_for_mechanical_engineering.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_off0000fec2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEC2 5800 bytes
SHA-256: 322f5068b9eea54cce9d78f9b9049be4ea63136e16d342d2d1a3cbb4fc3dba7d
font_01_sfnt_off000112a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112A4 11452 bytes
SHA-256: d5a32ca1973c3d4241ccb23a4c319ec553f5bbc18ccd8e2e6bc2fff9f8571556