Malicious PDF — malware analysis report

Static analysis result for SHA-256 533d8c58a1ebf20f…

MALICIOUS

PDF

106.6 KB Created: 2021-06-28 22:23:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 80e13f065bb0022a60bcb1faf70702f4 SHA-1: 79e40d36c37630135b9090de610f21a7226965da SHA-256: 533d8c58a1ebf20fa61b831a90b34607477073b5d1ac935e2bad4f8fc5df53ba
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous links pointing to compromised WordPress upload directories and disposable hosting, suggesting it is part of a link farm designed to redirect users to malicious sites. The primary purpose appears to be directing users to external, potentially malicious, URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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://allytemp.ru/uplcv?utm_term=theridiid+tangle+web
    • http://www.pianoszimmermann.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608da23c25eba---9521466356.pdf
    • https://wickedcheesy.com/images/file/98713309478.pdf
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070e82419b2c---2655557757.pdf
    • http://www.communityheroesproject.org/wp-content/plugins/formcraft/file-upload/server/content/files/16086cf8ce2652---powibofapanixujig.pdf
    • https://hyosungulf.com/uploads/file/nobomukarezenudoder.pdf
    • http://wildpflanzen-planung.de/file/xenesuwetakatutamux.pdf
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/b3141acec87dc7a2980bf1c90ccbe069/rukumofegenebaxomu.pdf
    • http://bmcnx.com/userfiles/file/74081311536.pdf
    • http://blog.crowdly.com/wp-content/plugins/formcraft/file-upload/server/content/files/160949b7353e98---kasatasog.pdf
    • http://teifsepahan.com/files/file/jabufajozasusilejabidifi.pdf
    • http://files.ibiza-ferien.de/file/21411639319.pdf
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/06sp32l7gcvudbn5ip2fr55887/duzetejejo.pdf
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/cb3b1a925b5eb6e9d348a7220728ee19/53525282589.pdf
    • https://njsolarpower.com/wp-content/plugins/super-forms/uploads/php/files/a17e4d7c44ee8f7c02371f5dc229a44a/dutorozov.pdf
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2b8cef02a5---52914103744.pdf
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/160ab948e307fe---wofewuludinidakar.pdf
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/44jp43183s0dt6115j3jcestq4/votugu.pdf
    • https://realestateconnect.us/wp-content/plugins/super-forms/uploads/php/files/v2ija0qrs83ug2q7n9025697s1/jisipozupoguri.pdf
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b76b73990e9---58242201072.pdf
    • http://veterina-hrib.cz/user-uploads/files/1315464589.pdf
    • https://advance-pack.com/editor_upload/file/lejazusivipibaj.pdf
    • http://beijinghuojia.cn/userfiles/file/kaxiwixugewamowegepivuva.pdf
    • https://alamansyria.com/userfiles/file/32882939624.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_off00013ccb.bin
e58e6bf3787479e2f40e4d3d95e7b995c45f05c0456498044e0049309d153319
pdf-font-stream PDF embedded font (sfnt) at offset 0x13CCB 18844 bytes
font_01_sfnt_off00016dfd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x16DFD 16792 bytes
font_02_sfnt_off00018614.bin
afcee9bc3c0a2965aa4c25046018a6c9f68a8fd76b6fc481491775f528ed2cff
pdf-font-stream PDF embedded font (sfnt) at offset 0x18614 10428 bytes