Malicious PDF — malware analysis report

Static analysis result for SHA-256 c26c727fc6e6c639…

MALICIOUS

PDF

79.6 KB Created: 2021-03-31 06:33:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 679bcf01484609ee65e00aaebb6397aa SHA-1: c4beffa8bb686acb38a3035d73504d7237ac4c7d SHA-256: c26c727fc6e6c6390161c314e61978ba0f330c5f6c1e1b281a81cf0196f0c7e3
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1105 Ingress Tool Transfer

The PDF file contains a large number of external links, many pointing to disposable domains and Weebly-hosted files, indicating a link farm or SEO manipulation tactic. Heuristics like 'PDF_SEO_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggest this purpose. The ML classifier and ClamAV detection further support its malicious nature, likely as a distribution point for other malicious content or phishing lures.

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://xezojetit.ru/award?keyword=l%25C3%25B6sen+von+gleichungen+aufgaben+pdf PDF link annotation
    • https://lepudumewo.weebly.com/uploads/1/3/5/9/135962044/sulisoz-sosul-rugigug.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454825/normal_600fe19b4e689.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4465685/normal_603aeaabd16fc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4386074/normal_601cd4e989716.pdfIn PDF document text
    • http://vkysnaya-eda.site/91390835356548wy.pdfIn PDF document text
    • http://pokemonrivals.online/lalesofo4g9ld.pdfIn PDF document text
    • https://mosodufenu.weebly.com/uploads/1/3/4/8/134889918/sujevirokeruliritori.pdfIn PDF document text
    • https://vepimogarib.weebly.com/uploads/1/3/4/8/134856589/mofidodexuwujif.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4480408/normal_60030b8f25abd.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4457011/normal_603349a91899e.pdfIn PDF document text
    • https://widosogepe.weebly.com/uploads/1/3/3/9/133986955/751188.pdfIn PDF document text
    • https://tizizuner.weebly.com/uploads/1/3/1/8/131872037/127c7743c7.pdfIn PDF document text
    • http://kino-vezde.ru/what_are_the_different_phases_of_mitosiss25k8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385410/normal_604b997024421.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450640/normal_600a0677ec85c.pdfIn PDF document text
    • https://jafoxexaromomev.weebly.com/uploads/1/3/5/2/135296472/2e4a2510e2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4387424/normal_605c927fafe3b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420235/normal_604a52af7df37.pdfIn PDF document text
    • https://xonajababivoxo.weebly.com/uploads/1/3/4/0/134040492/weruxelos.pdfIn PDF document text
    • https://kufoxigokutef.weebly.com/uploads/1/3/1/8/131856815/7834700.pdfIn PDF document text
    • http://winoraama.fun/top_paid_android_apps_in_play_storesdsgp.pdfIn PDF document text
    • https://nefupoxuwuridek.weebly.com/uploads/1/3/4/7/134747690/5883081.pdfIn PDF document text
    • http://psylath.com/52684723046ihq2c.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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_off0000f2c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2C0 5600 bytes
SHA-256: 2e0153edeba5ef91d90d18e8b66ef420efb97fc66a2ca557b826052cd06fec8b
font_01_sfnt_off00010595.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10595 12612 bytes
SHA-256: 399692c52f84ec7633d1f63fb76eeb7b9cf33a1a066ab92826edaefed02c294a