Malicious PDF — malware analysis report

Static analysis result for SHA-256 93d9efb11eab9c28…

MALICIOUS

PDF

78.1 KB Created: 2021-03-22 18:24:27 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: adf85ddfd206985f88041971c186c2e0 SHA-1: 9136deba4004cebdf6252386400171e0a405d632 SHA-256: 93d9efb11eab9c28f610c8d8107ae8d614b99ac92fc8226a117e86cd67dce25b
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to seemingly benign PDFs, but also includes a link to vilenefex.ru which is suspicious. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and link farm suggest it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 5

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://vilenefex.ru/wix?keyword=study+guide+questions+and+answers+for+the+giver
    • https://tifowufiwadoxi.weebly.com/uploads/1/3/4/0/134098290/8916593.pdf
    • https://cdn-cms.f-static.net/uploads/4485173/normal_601e499460a90.pdf
    • https://pegugigatusib.weebly.com/uploads/1/3/4/4/134460290/8298174.pdf
    • https://dufadijikog.weebly.com/uploads/1/3/5/3/135325035/webanijoxaxa.pdf
    • https://favadela.weebly.com/uploads/1/3/1/0/131070298/vefusi.pdf
    • https://nabesoke.weebly.com/uploads/1/3/4/0/134042749/pejarewifupef_mafakawevo_derep_gisemakiga.pdf
    • https://tiwofimobodes.weebly.com/uploads/1/3/4/0/134040820/denivas.pdf
    • https://cdn-cms.f-static.net/uploads/4485589/normal_602726f16bd7b.pdf
    • https://kigusokitog.weebly.com/uploads/1/3/5/3/135300221/wefenigusumel.pdf
    • https://gatakuluva.weebly.com/uploads/1/3/1/8/131856326/gelef.pdf
    • https://dubobovutorikug.weebly.com/uploads/1/3/5/3/135332124/bepukaj-redizejapovuzit-zumiweziwon-fozarafemoli.pdf
    • https://xulejodamujodu.weebly.com/uploads/1/3/4/7/134771271/lobenetu-sakolujejimoj.pdf
    • https://dubakaxejevam.weebly.com/uploads/1/3/2/6/132696109/34fb82b1.pdf
    • https://lifefoxametuzov.weebly.com/uploads/1/3/1/3/131383893/lipoz_zuver.pdf
    • https://ruwivogisi.weebly.com/uploads/1/3/4/2/134265822/6a4033610.pdf
    • https://zirodamabesad.weebly.com/uploads/1/3/0/7/130740068/9076624.pdf
    • https://risegutu.weebly.com/uploads/1/3/4/2/134265716/4036312.pdf
    • https://nezokamovijemi.weebly.com/uploads/1/3/1/8/131856769/kowiwopekunaw-kilululabexo.pdf
    • https://kadezejuvi.weebly.com/uploads/1/3/4/6/134603763/a9c5d7.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/pusori/xawarimubulix.pdf
    • https://s3.amazonaws.com/zafibimutadoti/rereading_america_10th_edition_free.pdf
    • https://s3.amazonaws.com/tosevud/70549805430.pdf
    • https://s3.amazonaws.com/wupixufekijax/jufijewojuxevepojiralofev.pdf
    • https://s3.amazonaws.com/kizugokofo/linek.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f339.bin
605d71f5a91eccb89ac0d3ae1ad41d45f1b256452e11914d9900fadcc7a72815
pdf-font-stream PDF embedded font (sfnt) at offset 0xF339 5620 bytes
font_01_sfnt_off00010669.bin
fd9476b44a6e4412afee89cacccafd6a6dca5be2448cb5c3a3b228b22e9f9fe0
pdf-font-stream PDF embedded font (sfnt) at offset 0x10669 10536 bytes