Malicious PDF — malware analysis report

Static analysis result for SHA-256 0d3674d2ed58387e…

MALICIOUS

PDF

78.2 KB Created: 2021-05-20 01:18:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 3b3434fba2948f5814c4cc47cead8a2a SHA-1: ea144ce723bf1d13ae0e646b4eefe9268a8fde00 SHA-256: 0d3674d2ed58387eb698238f942ebb36b6c53caf15b3b32f2f52974820f18998
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF contains a large number of external links, many of which point to seemingly unrelated content, indicating a link farm or SEO poisoning attempt. The primary malicious URL, https://jumiwimov.ru/strik, is presented within the document body, suggesting a phishing or malware distribution lure. The presence of PDF-specific heuristics like PDF_URI and PDF_SEO_LINK_FARM, along with a high ML classifier score and ClamAV detection, strongly indicates malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://jumiwimov.ru/strik?utm_term=icse+class+10+chemistry+questions+and+answers
    • https://sunajekivogemaz.weebly.com/uploads/1/3/4/8/134895881/wetoburunu-banazijokozava.pdf
    • https://zexaloguf.weebly.com/uploads/1/3/4/5/134576330/a78d1b3bade6.pdf
    • https://kajizifobizixa.weebly.com/uploads/1/3/3/9/133997117/9366713.pdf
    • https://cdn-cms.f-static.net/uploads/4384037/normal_5fe962f084f21.pdf
    • https://jagusidenoz.weebly.com/uploads/1/3/4/9/134902343/tojup_nelugiletos_xetero_fiwelivevoz.pdf
    • https://cdn-cms.f-static.net/uploads/4366376/normal_60248842a6e1b.pdf
    • https://puliwive.weebly.com/uploads/1/3/4/6/134660228/latix.pdf
    • https://xuwosanilenerev.weebly.com/uploads/1/3/4/9/134900173/4382766.pdf
    • https://xabetidadema.weebly.com/uploads/1/3/1/3/131398123/lofawovu_lurikivetivemit_kunabipubolose_zelona.pdf
    • https://static.s123-cdn-static.com/uploads/4420438/normal_5fceda8d7bba2.pdf
    • https://gujuwazadux.weebly.com/uploads/1/3/2/3/132303410/1526457.pdf
    • https://pulatufulufu.weebly.com/uploads/1/3/4/6/134610330/lisetofubuz.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/vovopafubipu/centos_6._7_32_bit.pdf
    • https://s3.amazonaws.com/gogoxowiniza/81988755717.pdf
    • https://s3.amazonaws.com/telasebisu/dowizimewurukawesolirorip.pdf
    • https://s3.amazonaws.com/muvazi/38905311007.pdf
    • https://uploads.strikinglycdn.com/files/15164494-07bd-4132-8135-0927f9c4872a/7.3_similar_triangles_worksheet_answers.pdf
    • https://uploads.strikinglycdn.com/files/66f0b835-bb0a-44e9-a319-c9529f85d7c8/fedex_near_san_antonio_airport.pdf
    • https://s3.amazonaws.com/vikukinumet/70145453723.pdf
    • https://s3.amazonaws.com/bepukuba/joint_variation_examples.pdf
    • https://uploads.strikinglycdn.com/files/2804ffdc-9fe7-4e8b-ab4f-fa6a60c31961/sears_lawn_mower_repairs_service.pdf
    • https://uploads.strikinglycdn.com/files/19a63278-0f54-4280-9c20-be17de05de13/47184580044.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_off0000f50a.bin
a00a4d5baf17596bf9e83cda3cbf8e2b54c32a1f0cc2cd5445805aba0d64b90f
pdf-font-stream PDF embedded font (sfnt) at offset 0xF50A 5628 bytes
font_01_sfnt_off00010815.bin
1a6f978c2ec907705a4d4c7c98019a5923697dff9b971c61d5fa9b9041455bdf
pdf-font-stream PDF embedded font (sfnt) at offset 0x10815 10160 bytes