Malicious PDF — malware analysis report

Static analysis result for SHA-256 3db0acb0967d5501…

MALICIOUS

PDF

78.2 KB Created: 2021-04-29 14:24:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: e9238a1ea7f1fe50648e972986717a38 SHA-1: 2f44a4faff34b580e87e5aa4a71fc2c45632a2aa SHA-256: 3db0acb0967d5501d798619322f201a109c2ef630b09e201de5e952655f04ebc
206 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, indicating a link farm or SEO manipulation tactic. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the presence of malformed streams and external URIs points to exploitation or redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • 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://pelibifir.ru/strik?utm_term=are+nordic+spas+any+good PDF link annotation
    • https://kuvinonufero.weebly.com/uploads/1/3/4/3/134307364/6087716.pdfIn PDF document text
    • https://cdn.sqhk.co/gewanunu/Qy5hgic/nascar_super_speedways.pdfIn PDF document text
    • https://cdn.sqhk.co/sojetaji/gjw0YD9/buzz_cut_with_beard_fade.pdfIn PDF document text
    • https://kadorupadidugi.weebly.com/uploads/1/3/1/6/131636929/sugeg.pdfIn PDF document text
    • https://fujazilumekopel.weebly.com/uploads/1/3/2/6/132681311/zisenof-kelawekudinumes-vajerufusodori-tilajonefufebi.pdfIn PDF document text
    • https://soregekewo.weebly.com/uploads/1/3/4/2/134266411/wesexemokekaboz-tejolorot-vakaterewafej-tudekurulipim.pdfIn PDF document text
    • https://cdn.sqhk.co/puwidebudojo/jhqhjja/dusoviralide.pdfIn PDF document text
    • https://cdn.sqhk.co/febowozefu/agh9oCA/mirror_salon_ridgefield_wa.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://perexuwofogefo.onlinewebshop.net/what_is_better_a_single_stage_or_two_stage_snow_blower.pdfIn PDF document text
    • https://981168d4-05fc-44b6-871d-73371d7e8cf1.filesusr.com/ugd/87d215_6583a07099b844d284c2614cc60c473d.pdf?index=trueIn PDF document text
    • https://3a00e800-a8eb-44ae-aafc-ae9aecab8e06.filesusr.com/ugd/1715bf_fbb85ae11c2640cd909d2f3c839e71ed.pdf?index=trueIn PDF document text
    • https://73f4d879-981c-49fe-abc7-520f36a14a84.filesusr.com/ugd/b77b08_14fd963cf9af4187ac054bb14c977f70.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/xopugup/21526173283.pdfIn PDF document text
    • http://jimarol.myartsonline.com/50417265566.pdfIn PDF document text
    • https://s3.amazonaws.com/timituvupame/fixis.pdfIn PDF document text
    • https://73e25548-3913-4bbb-aa69-a1b25f69568d.filesusr.com/ugd/cece23_f829c32de3f24a6890bbd48db8fb0004.pdf?index=trueIn PDF document text
    • https://ffb80149-315c-4936-8637-e87477b606fc.filesusr.com/ugd/e7410d_523af8b7abf940f3bac0303545b9c594.pdf?index=trueIn 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_off0000f345.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF345 5300 bytes
SHA-256: 26801aa3dd430831f3ae88de837d488ae6c9060ad5af6bbcdb7f50d205edd24b
font_01_sfnt_off00010567.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10567 11288 bytes
SHA-256: a5245f2d41cc9810992e09c5dcece4861d1035fa94a14dbc3a331ca8958a1b51