Malicious PDF — malware analysis report

Static analysis result for SHA-256 b56c4b846621c808…

MALICIOUS

PDF

79.6 KB Created: 2021-03-29 09:00:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: add1c983c0900d3469baba76ee878f3c SHA-1: 609f4da98268eac1651c7a449bf5a1de58434294 SHA-256: b56c4b846621c8089c0f5e837f7dd25240e617a42729b27484f671e176cd9932
186 Risk Score

Malware Insights

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

The sample is a PDF document identified as malicious by ClamAV and an ML classifier. It functions as a link farm, containing numerous external URLs, with one prominent URL pointing to 'fokemale.ru'. The PDF structure and the presence of multiple external links suggest an attempt to redirect users to potentially malicious sites, likely for phishing or malware delivery. No scripts were extracted, but the overall behavior aligns with a malicious document designed to lure users to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • 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://fokemale.ru/strik?utm_term=white+tiger+masked+singer+judge+guesses PDF link annotation
    • http://bupro.asia/56390383149ruhwz.pdfIn PDF document text
    • https://cdn.sqhk.co/wupofolizaj/jhfo1je/tmnt_rooftop_run_free_down.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4388416/normal_601c9942efe27.pdfIn PDF document text
    • http://drnextact.xyz/63426439909a3vbw.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4450507/normal_5fde6dfded82c.pdfIn PDF document text
    • https://cdn.sqhk.co/wirowanorax/Cjjhgd1/wakenewugewasodifamuzakiw.pdfIn PDF document text
    • http://1offpark.xyz/swanns_way_moncrieffhyw5v.pdfIn PDF document text
    • https://cdn.sqhk.co/jusitufugaf/ihhcaY4/96465300810.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://89e5ed4a-33eb-42a6-b5f1-9fc07ea1e15b.filesusr.com/ugd/ff68bb_3f23be7c979548368e6bb2c1a2d86322.pdf?index=trueIn PDF document text
    • https://02314edc-d025-420b-9d62-795437f25c47.filesusr.com/ugd/4f0fc1_371007f341f4422382dfc03c829d21db.pdf?index=trueIn PDF document text
    • https://625f08e2-3d8e-45b5-8e8c-b95d001c5c7c.filesusr.com/ugd/d94ae5_51131492999e4010aee91d5bc2c5be52.pdf?index=trueIn PDF document text
    • https://1628ddcf-e301-416d-9649-d9339b85441b.filesusr.com/ugd/0b1079_f704f128a18e4328972a9484a292b1dc.pdf?index=trueIn PDF document text
    • https://115777a2-cc0e-4789-9e99-30cf4bdfca1a.filesusr.com/ugd/2b3546_c16e9507e25a4d8b9b298c25000e7904.pdf?index=trueIn PDF document text
    • https://0bdb67af-4c57-4a6e-9706-714cc80719f5.filesusr.com/ugd/fc840b_d06f19af39c44b8ea1a9b418cf7432ac.pdf?index=trueIn PDF document text
    • https://694dae7a-2033-4a59-8b06-91ff4eec0774.filesusr.com/ugd/e1d58f_9edc4d081b784ab3acd2082fc5d5e098.pdf?index=trueIn PDF document text
    • https://98e80eac-0673-4bf9-a3de-4132461903b3.filesusr.com/ugd/1acd69_1c1858ade5d841738f7d8a2443a42e9b.pdf?index=trueIn PDF document text
    • https://86f5e18a-8766-4ae7-b9bf-31430b627380.filesusr.com/ugd/911c12_5c6457a3b4d34e7bbbc20b117899f979.pdf?index=trueIn PDF document text
    • https://645c32c3-7e99-4959-b93b-7980205539d7.filesusr.com/ugd/30a31c_79e0bf08eaf5463682420777f6d6266f.pdf?index=trueIn PDF document text
    • https://5c2df1de-05ea-4e17-9aa3-38adc7ce3153.filesusr.com/ugd/ddd609_5e04a44f8d3c43a985547fbb11cc48e9.pdf?index=trueIn PDF document text
    • https://39c1d623-eccb-4af0-a86a-15328a2d61f9.filesusr.com/ugd/3cb6cb_d03a2c5d1b3840f3b75ee236a1dd5333.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_off0000f5a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5A7 5360 bytes
SHA-256: ccca1b2508329e826f2c3a3cc7450d0737586a3219d984ac7ad973c589d1ef79
font_01_sfnt_off000107c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107C6 11928 bytes
SHA-256: 639aced5dffd125a1553101b305481a2520b882318efe30ee2872175a18a0630