Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5981a9f87065330…

MALICIOUS

PDF

89.4 KB Created: 2020-11-18 12:50:40 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f42072da1d58d6ff6272df2fe8ccee8f SHA-1: 7b32b97b4187ff7d05a87f98f6c82e0c6d732b34 SHA-256: c5981a9f870653300171bafcc87eed63023347045d042334ca43b39d373877c8
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a large number of external links, many pointing to PDF files hosted on platforms like Weebly, suggesting a link farm or distribution network. While no scripts were explicitly extracted, the PDF structure and the presence of numerous external URIs indicate an attempt to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://trafficel.ru/123?utm_term=bach+chaconne+harmonic+analysis
    • https://nolaxefipox.weebly.com/uploads/1/3/4/7/134740184/2063377.pdf
    • https://mogoribomos.weebly.com/uploads/1/3/4/2/134266362/8007453.pdf
    • https://xifobosakup.weebly.com/uploads/1/3/2/8/132815359/ec78fffbd8.pdf
    • https://luletifolavok.weebly.com/uploads/1/3/4/3/134369244/5b1b5c30bcd8a.pdf
    • https://wedebiki.weebly.com/uploads/1/3/0/9/130969436/witowuje_fumegafukusat.pdf
    • https://cdn-cms.f-static.net/uploads/4380531/normal_5fa355e71a395.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/12940ff9-def2-4267-af89-3866f23d2ea7/ruzivurotodig.pdf
    • https://uploads.strikinglycdn.com/files/72b93d7f-b994-4970-9490-7d727545ac03/xotawojugaxexoba.pdf
    • https://uploads.strikinglycdn.com/files/460c1e35-01d9-476e-ba17-fc07908a90bd/5391811716.pdf
    • https://uploads.strikinglycdn.com/files/2dfba7ac-0c5c-42bb-a89c-009c6efa0c8c/brighton_beach_memoirs.pdf
    • https://s3.amazonaws.com/vudivuzakal/ut_lady_vols_basketball_online.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
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010b0d.bin
969950f743fe9532bcf6c8c304d8178cf7ec96f7dc96a98fdd87e304bf4664ea
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B0D 5192 bytes
font_01_sfnt_off00011c90.bin
9135c89080211c0e76957bb385a91ae0f70cc589234724a09d6b54d481e2040d
pdf-font-stream PDF embedded font (sfnt) at offset 0x11C90 11420 bytes
font_02_sfnt_off000143de.bin
46d9b83afd797048ab251ddfc9ca9a6db44f3280724c231f6a80a061bcc6fc12
pdf-font-stream PDF embedded font (sfnt) at offset 0x143DE 16120 bytes