Malicious PDF — malware analysis report

Static analysis result for SHA-256 79a9056bdd40b1c3…

MALICIOUS

PDF

86.2 KB Created: 2021-05-01 20:36:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-17
MD5: c6a4f1a70e0c17d9ef218ce0b0dbdf16 SHA-1: b24f3dee171e56b8167f6f89111eb8fa511066ea SHA-256: 79a9056bdd40b1c31bb34f41eea49663f90af5ef4332fafd10486834dda07713
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a large number of external links pointing to various domains, many of which appear to be disposable hosting. This behavior is indicative of a link farm, likely used for SEO manipulation or to distribute further malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, with the primary technique being the distribution of links via a document.

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://jacksth.ru/strik?utm_term=is+egyptian+arabic+hard+to+learn PDF link annotation
    • https://gomadiwisedewun.weebly.com/uploads/1/3/5/3/135314557/6bbab5ed4.pdfIn PDF document text
    • https://cdn.sqhk.co/kinanekoxo/IGihmid/tukurojekenugufamidejazi.pdfIn PDF document text
    • https://cdn.sqhk.co/xumirikebixo/ISigkjh/mini_golf_challenge_app.pdfIn PDF document text
    • http://kosonetibekub.medianewsonline.com/lebukuraniwot.pdfIn PDF document text
    • https://gasuzenop.weebly.com/uploads/1/3/4/2/134266144/masagikoz-wuwugenekizigog.pdfIn PDF document text
    • https://cdn.sqhk.co/kufalavoxig/K1jfDne/85157679033.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379982/normal_605d93b06679e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4405644/normal_601955fbe645c.pdfIn PDF document text
    • https://cdn.sqhk.co/susiwebuvowo/ibagl1q/miwuwa.pdfIn PDF document text
    • https://cdn.sqhk.co/vudupapuj/h3YeXhc/red_button_ginger.pdfIn PDF document text
    • https://pofemazavuson.weebly.com/uploads/1/3/2/3/132303373/4533655.pdfIn PDF document text
    • http://wifunagidoli.mypressonline.com/libro_gramatica_y_ortografia_basica_de_la_lengua_espaola.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4409092/normal_5fc5ffa97b563.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://8d928d4c-4e32-4dc6-8093-d383c90b3cca.filesusr.com/ugd/b5d49c_aa5954d0c00b45069e036c5f9c3789b7.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/456046e1-a109-4ddd-9aec-343904417062/tatamimijenikiler.pdfIn PDF document text
    • http://wutesejib.onlinewebshop.net/kovukigatuvopewo.pdfIn PDF document text
    • https://f9cb7010-568c-45d0-b0a5-7bd630b60272.filesusr.com/ugd/b10ea2_8a0788d5601f4b3d905697992e4c2dc5.pdf?index=trueIn PDF document text
    • https://6f4861c6-cdf0-4a5f-ba2d-f9c5e5bfbee6.filesusr.com/ugd/77941b_92407490c7974ab58591fc0fddc74839.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/7a046cbb-07c9-4315-ad88-d1c9ce10efa4/thermos_grill_2_go_fire_and_ice_price.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_005_off000120fb.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x120FB 24056 bytes
SHA-256: e6a14568a18442d45858f149c9c27cb6fc3a446d9f4a67c527297fe8ae7993e5
font_00_sfnt_off0000eaa8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAA8 5512 bytes
SHA-256: bd8c6ce6e88be21b21ecb2c0e23adedece407cc8a5f4b2b3dcd6830e8e380d26
font_01_sfnt_off0000fd5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD5D 10456 bytes
SHA-256: fa2787b14386028f6d93be2a921c10a8c66b2c4cd7f7eab199d8c9d3cb1e0f82