Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f917f80ba83f72d…

MALICIOUS

PDF

111.9 KB Created: 2021-03-29 08:04:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: e11fa811e0ead0af6298e898404de0f1 SHA-1: b81e0b5530932e09cb2dfc7ad489e3e5fd08bf2b SHA-256: 8f917f80ba83f72d9abb6d08fc065bc7f1061ae0fbf9d5bde93050f4203d655d
194 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses an urgency-based lure. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

Heuristics 7

  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://zajinet.ru/award?keyword=best+pdf+markup+app+windows+10 PDF link annotation
    • https://cdn.sqhk.co/xotosira/iL0kmhg/free_kicks_world_cup.pdfIn PDF document text
    • https://cdn.sqhk.co/rumobotituda/7vfVjjh/how_to_bold_textview_in_android_studio.pdfIn PDF document text
    • http://valamivu.22web.org/pivilozudivanaxofivetozot.pdfIn PDF document text
    • https://cdn.sqhk.co/sezepemanu/jcP8pgj/65747938411.pdfIn PDF document text
    • http://dafomexo.22web.org/addictive_drum_2_full_version_gratis.pdfIn PDF document text
    • https://cdn.sqhk.co/vugomupuzisa/jhNcdii/kajirotib.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • http://xilawon.epizy.com/88267223020.pdfIn PDF document text
    • https://041aa876-b65b-432c-96c0-58c8b295a4e4.filesusr.com/ugd/90d19e_cecdd25ef9c044279383f640be2f0448.pdf?index=trueIn PDF document text
    • https://67258aaf-84c5-4a88-bfd2-1aa7ddb6c27a.filesusr.com/ugd/850f07_65c6a4ee1e864d65b71f838dd7059f5f.pdf?index=trueIn PDF document text
    • https://f459ab6e-ac57-43ce-b83a-1524846427e4.filesusr.com/ugd/938c70_3a611c1abf3449169d0b62fd4e5c140a.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/490496de-e5ca-41cf-956d-f0f09b5baa93/xowibekivigunisebunenubew.pdfIn PDF document text
    • https://656adf98-7a81-40bd-8d0f-2b9c27d09201.filesusr.com/ugd/268ab1_ff5df869838d4498bcc382876951ec0a.pdf?index=trueIn PDF document text
    • https://6323cc82-cf72-43ae-bc7a-f8d691a1d37e.filesusr.com/ugd/4f3578_09f90d9203504acc8caa6db77c169e82.pdf?index=trueIn PDF document text
    • https://502e425a-54a0-4661-a3e6-c6e116bdb13d.filesusr.com/ugd/10da26_7b2c8a58868c487aa259596d587215b0.pdf?index=trueIn PDF document text
    • http://sulosuduvemog.epizy.com/20886602242.pdfIn PDF document text
    • https://s3.amazonaws.com/gezetega/zenazurupejoxuvoxituneru.pdfIn PDF document text
    • https://s3.amazonaws.com/rovikibixu/mopuxo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/42d0f533-71d7-4db9-94ab-c28a5410854f/bisatowewesunumeme.pdfIn PDF document text
    • http://dosujag.rf.gd/fijaselazimiwot.pdfIn PDF document text
    • https://b5526579-b22d-45a0-8251-9885a72cf3eb.filesusr.com/ugd/0cd019_b326389c6b6f4d1aa3875120161ac5c9.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/ee8cf55f-ee3e-46b7-a91e-7739d055df89/krk_rokit_g2_vs_g3.pdfIn PDF document text
    • https://557345b1-98c6-442d-b460-9e357c178e5b.filesusr.com/ugd/dfb5f8_b26580c4ea1d4916818e49e27c54656c.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/4bb70738-3a3f-4ee2-a8d9-7821abccc70a/28928816707.pdfIn 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001695d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1695D 5436 bytes
SHA-256: 8f5fc4cdf0359464ef7a67d8bbbe4e44fa2688048362d6e13c97139c216c5b91
font_01_sfnt_off00017bd2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17BD2 11632 bytes
SHA-256: 2a504ecd8864319d809ac7303ad354cfdf49c9e0976b7086c1c7f91cca99b18c
font_02_sfnt_off0001a344.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A344 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34