Malicious PDF — malware analysis report

Static analysis result for SHA-256 9b51da3aec77a5a5…

MALICIOUS

PDF

68.4 KB Created: 2021-09-28 18:08:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d2f8acaf2f4dd6871fccc7898ee8fe23 SHA-1: c0d4c8573830fa74432ec6102e44704efe842192 SHA-256: 9b51da3aec77a5a59352392a74e59f82b837e89a730c772e2baa991d43fe418f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs pointing to various domains, many of which appear to be compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document's structure as a link farm suggests an attempt to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://philabc.ru/uplcv?utm_term=vidmate+apk+all+version
    • http://nikolalepojevic5.com/multimedia/file/54669853528.pdf
    • http://csc025.com/userfiles/file/20210904160346_yrigiz.pdf
    • https://onthespothousing.com/userfiles/file/xisodapi.pdf
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/161361d3152c0d---3356898971.pdf
    • http://viral-list-machine.com/ckfinder/userfiles/publics/files/16371883482.pdf
    • http://2sisaccount.com/userfiles/files/legumiba.pdf
    • http://www.pattyn360.com/upload/forum/files/muralusazuv.pdf
    • http://mikailang.com/userfiles/file/20210907130217_1267736295.pdf
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1613fe6029b04f---90560839174.pdf
    • http://xn--m1age8bh.xn--p1ai/files/file/83434249101.pdf
    • https://cribpointonline.org/cribpointonline/userimages/file/81778066639.pdf
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/a88f335adcbe65c4b5fbda9c213beb3f/vutukodikemurevewixudupem.pdf
    • http://assessmentinsight.com/ckfinder/userfiles/files/ludexetoraxosezit.pdf
    • http://boilerservis.ru/uploads/files/togemitupikaxaxoto.pdf
    • http://pavcargo.ru/wp-content/plugins/super-forms/uploads/php/files/4807ab6983c1356cf124593ac8d97b12/17521189960.pdf
    • http://tootingtaxi.com/survey/userfiles/files/tideluzoratugarapewasozi.pdf
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/1614d34cc654c8---ratubulexibojiji.pdf
    • http://deforma.it/userfiles/files/4007105283.pdf
    • http://e-menu.hu/editor_up/25505261206.pdf
    • http://suamanhinhlcd.net/userfiles/file/49992115431.pdf
    • http://www.nbc.com.vn/ckfinder/userfiles/files/sunenup.pdf
    • http://propertiesforrent.com/userfiles/file///rodukesukepalarixutib.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://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_off0000ae29.bin
75d4ca1116dff9257a24a9199af80a77381c1dff52a683ae0d99912f95168e43
pdf-font-stream PDF embedded font (sfnt) at offset 0xAE29 10680 bytes
font_01_sfnt_off0000c69f.bin
48a6b6871735420d71961372626582053fea3d538b167e7a0cd6958b51e02193
pdf-font-stream PDF embedded font (sfnt) at offset 0xC69F 14944 bytes
font_02_sfnt_off0000ec8d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC8D 16792 bytes