Malicious PDF — malware analysis report

Static analysis result for SHA-256 11142d4e3f621c12…

MALICIOUS

PDF

82.8 KB Created: 2021-05-28 20:54:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ae79560279326c9ecd39b744a5294803 SHA-1: 9125b1c91b9b21e195debdc00741f538ee2ac6cd SHA-256: 11142d4e3f621c122a11db7e70663ef8a9a92041c521fff045d2aebc04273568
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 of which are hosted on link farms, indicating a phishing or spamming operation. The primary URL, 'https://jacksth.ru/strik?utm_term=conjugacion+de+verbos+irregulares+en+espa%25C3%25B1ol+pdf', suggests a lure related to Spanish verb conjugations to entice clicks. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for malware distribution or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9967

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-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://jacksth.ru/strik?utm_term=conjugacion+de+verbos+irregulares+en+espa%25C3%25B1ol+pdf
    • https://cdn-cms.f-static.net/uploads/4412763/normal_600c68dfc7039.pdf
    • https://falijufik.weebly.com/uploads/1/3/5/3/135349852/4dcd5314492.pdf
    • https://cdn-cms.f-static.net/uploads/4378381/normal_5fd7783723b59.pdf
    • https://lewuroluloxujul.weebly.com/uploads/1/3/4/6/134678017/bawafazaranub.pdf
    • https://nebijuwako.weebly.com/uploads/1/3/4/3/134376342/5448017.pdf
    • https://lubagevaruzazej.weebly.com/uploads/1/3/2/7/132712663/7774846.pdf
    • https://cdn-cms.f-static.net/uploads/4390684/normal_605a771489f81.pdf
    • https://cdn-cms.f-static.net/uploads/4421199/normal_60434391554cf.pdf
    • https://zugufavowi.weebly.com/uploads/1/3/0/8/130874222/899a32c70f.pdf
    • https://bogezemobazuv.weebly.com/uploads/1/3/1/8/131856224/japolodonuvejosizo.pdf
    • https://pifeposanitu.weebly.com/uploads/1/3/4/7/134753567/wogokimo.pdf
    • https://cdn-cms.f-static.net/uploads/4496582/normal_5fd12b1279bbd.pdf
    • https://sivivaleretuvu.weebly.com/uploads/1/3/4/3/134324596/c3092e8.pdf
    • https://cdn-cms.f-static.net/uploads/4408593/normal_60676da732459.pdf
    • https://cdn-cms.f-static.net/uploads/4409806/normal_606258c85d60c.pdf
    • https://wetugaremuzen.weebly.com/uploads/1/3/5/2/135298520/duwuzodi.pdf
    • https://cdn-cms.f-static.net/uploads/4466398/normal_5fe9235937d9e.pdf
    • https://cdn-cms.f-static.net/uploads/4417308/normal_606cd5fa4250c.pdf
    • https://xopibazoditovo.weebly.com/uploads/1/3/1/4/131406935/84fe0a701b9.pdf
    • https://cdn-cms.f-static.net/uploads/4499282/normal_60418cf3d4a02.pdf
    • https://zikowipon.weebly.com/uploads/1/3/5/3/135300096/f07f7bc2.pdf
    • https://cdn-cms.f-static.net/uploads/4485162/normal_6044caafb754f.pdf
    • https://cdn-cms.f-static.net/uploads/4418197/normal_604f47bbc7f17.pdf
    • https://masevaru.weebly.com/uploads/1/3/5/3/135346062/5638777.pdf
    • https://cdn-cms.f-static.net/uploads/4450353/normal_601b772fde522.pdf
    • https://wanukepaxe.weebly.com/uploads/1/3/4/4/134454717/kabetorak.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • 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_off0000ffcb.bin
460ac6530166cff85f703a3bd693bb6f80061cbd5ca2738f18ccc762728ff0ed
pdf-font-stream PDF embedded font (sfnt) at offset 0xFFCB 5716 bytes
font_01_sfnt_off00011316.bin
4ce98121166008aeada7a5bc6017f30c9d4fe7dd27bd51c5995648660e2df6ad
pdf-font-stream PDF embedded font (sfnt) at offset 0x11316 12236 bytes