Malicious PDF — malware analysis report

Static analysis result for SHA-256 6ff542b31a422809…

MALICIOUS

PDF

71.9 KB Created: 2021-04-03 08:33:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d87f023ddf64e56e3db0ed2565eaaba4 SHA-1: d46af83c0298816d0a82cd71a6eeec493a9ea9a6 SHA-256: 6ff542b31a422809049b527632180010cd5030e629065edfbb1f8113509c78db
156 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many of which are disguised as academic research documents. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded URLs suggest an attempt to redirect the user to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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/award?keyword=amvisc+plus+pdf
    • https://fuwamelewupo.weebly.com/uploads/1/3/4/1/134131589/2170414.pdf
    • https://zanelonovubut.weebly.com/uploads/1/3/4/3/134315015/9465958.pdf
    • https://vuteduwezo.weebly.com/uploads/1/3/4/3/134336695/3890638.pdf
    • https://damafurota.weebly.com/uploads/1/3/5/3/135337485/bipanizu.pdf
    • https://ridakikasidom.weebly.com/uploads/1/3/0/7/130739592/komekigeruti.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/tixedujegibex/viwimapexafido.pdf
    • https://cccd2283-d272-450a-840b-6541230ebad2.filesusr.com/ugd/5de1df_3e5ba5c2769e4113bcbfd6b4aa526407.pdf?index=true
    • https://s3.amazonaws.com/zuxime/sevidozonovixixipujuw.pdf
    • http://siberasule.rf.gd/academic_achievement_research.pdf
    • https://s3.amazonaws.com/kefiperizonofu/36457290691.pdf
    • http://lejugilisotev.rf.gd/holy_bible_telugu.pdf
    • https://s3.amazonaws.com/gixirojozogufux/dekajanejesisakefonalotas.pdf
    • https://s3.amazonaws.com/fokapikow/46758895720.pdf
    • https://4993f9ff-345c-4c03-a8ec-d4f8dac664d6.filesusr.com/ugd/debbe1_eca04acd072d4e01a3d3f4d03fce5e0e.pdf?index=true
    • https://s3.amazonaws.com/gelawiweza/aditya_hridaya_stotra_in_kannada.pdf
    • https://s3.amazonaws.com/mukutud/kawibixoku.pdf
    • https://203aa715-7352-46b1-b16b-5d0aeeaa27a2.filesusr.com/ugd/0582e0_075590e5d3084f4aa7826c2f6fe282b4.pdf?index=true
    • https://s3.amazonaws.com/fusidejebi/book_review_outline_format_college.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_off0000dbb0.bin
2ddaba9773068347ef2108e32f01fc458e37b989aaa4abedc47db2496cd44d3f
pdf-font-stream PDF embedded font (sfnt) at offset 0xDBB0 5044 bytes
font_01_sfnt_off0000ecdb.bin
75cfbe85360d617af7c509b2a44a9d5b33b241f4a6b6f64b527bfc3ccfa212c8
pdf-font-stream PDF embedded font (sfnt) at offset 0xECDB 11080 bytes