Malicious PDF — malware analysis report

Static analysis result for SHA-256 6f7b9abd59563085…

MALICIOUS

PDF

68.1 KB Created: 2021-04-01 12:54:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 1598fe15bd421fae609ba2d18a1ea88f SHA-1: 3e7ff3f066014b7c497119f955ff59f284bf5f7f SHA-256: 6f7b9abd595630855bf3942973c8a93bce12d77ddcb72ce2f20a5ec6573964a5
186 Risk Score

Malware Insights

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

The PDF file contains a significant number of external links, identified as a link farm, with one prominent URL being resalured.ru. ClamAV detected this as Pdf.Phishing.Trojan, and ML classifiers also flagged it as malicious. The embedded content, though heavily obfuscated, suggests an attempt to redirect users to potentially malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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://resalured.ru/123?utm_term=angadi+theru+love+cut+songs PDF link annotation
    • http://punaweb.iblogger.org/how_to_open_files_on_kindle_paperwhite.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/fb77e0e3-6b54-4b97-ada3-eb792a39f45f/vimazuvuw.pdfIn PDF document text
    • http://vumujata.rf.gd/mokaja.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/11259d5a-23ab-41ec-802f-7501c55412d9/bissell_pet_hair_eraser_upright_vacuum_parts.pdfIn PDF document text
    • https://0a9dc515-c6d9-419f-b4de-d801a8c2a39b.filesusr.com/ugd/760a4c_7ee29b3f36534de287571bbf8e72225b.pdf?index=trueIn PDF document text
    • https://77483064-5892-4b52-b419-66e751946b77.filesusr.com/ugd/ef7b09_5d00d4a44e294fa9ab7a2901f0b8ba28.pdf?index=trueIn PDF document text
    • https://d2faa26e-66ca-44cd-8f84-883624a71019.filesusr.com/ugd/dbbfd0_0256d7f4ba7b4780b2fe4dada6532a89.pdf?index=trueIn PDF document text
    • https://070488ba-e3d9-4c74-834b-445551f5513c.filesusr.com/ugd/fb83f1_57fe519b0ef44780acc30fb3f36f8456.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/20572d49-f507-4f8a-bec6-d1457e17e758/chopin_24_preludes_henle.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b47f7579-3f6f-4d38-bd2f-8e1ec1a7f8e3/202417883.pdfIn PDF document text
    • https://a7193630-a032-4ee2-b136-33837135b76a.filesusr.com/ugd/fac845_e7af08d941ef4995a8122abee2757d8c.pdf?index=trueIn PDF document text
    • https://28a90398-13b1-4b58-b54c-ed045a6bddf2.filesusr.com/ugd/7e9e1f_84fbc427669c469a8d7dfe7bc15f19d4.pdf?index=trueIn PDF document text
    • https://9f1be152-2ea1-4306-981d-bfff62ad382d.filesusr.com/ugd/08fb22_6d88ca84e41e408a925f83919b45d4c6.pdf?index=trueIn PDF document text
    • https://76f5a3e5-08d8-4581-9975-6c1b933a1845.filesusr.com/ugd/dbbd16_5d168ec7b92a49bc9ff44377e4fa9ef0.pdf?index=trueIn PDF document text
    • https://60f6da8c-824c-4163-aae9-6195f2ac7ed4.filesusr.com/ugd/7f16bd_6a82df8161d840569855cb70e5d27415.pdf?index=trueIn PDF document text
    • https://27a83426-c768-4525-a63d-b5b732cca755.filesusr.com/ugd/28b3f7_f0e782d25f094504a7fc6ecbe7ea6024.pdf?index=trueIn PDF document text
    • https://f1fb087f-5d49-4061-aa02-230b108315d3.filesusr.com/ugd/645068_0288891a074a4dd9b95ac9f6b26b2669.pdf?index=trueIn PDF document text
    • http://raxaxeve.rf.gd/how_to_join_pakistan_army_medical_corps_after_mbbs.pdfIn PDF document text
    • https://2978fa49-077f-489e-bef2-0e177375ffd3.filesusr.com/ugd/50ba8f_55e95a27767e4d3e93e38990adb35dd5.pdf?index=trueIn PDF document text
    • https://58fabbca-0322-4868-a582-948aa19840f9.filesusr.com/ugd/93748c_ef1a420d005d4d5d8f3e3121e4194e89.pdf?index=trueIn 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cde6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDE6 5248 bytes
SHA-256: 23cd912b879ba2f24cdc165c8bb1b99afa3cacabb03c3903a913c00e45764b8b
font_01_sfnt_off0000dfc3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFC3 10436 bytes
SHA-256: 6e1239f2ee2a966f9809a07d13f086d2f0edc746a4da51740e2c7aa36abdce45