Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa99136361cc9add…

MALICIOUS

PDF

87.2 KB Created: 2021-06-26 17:31:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 474917ee3094b34c23f1c01a5e1d6a0a SHA-1: e8ef15ee973b6b40c20904001714ac52b08a403e SHA-256: aa99136361cc9add67a426bcd6ed139b345cd4ced3f09f7723e884c1f106eb35
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. ClamAV detected this file as 'Pdf.Phishing.Trojan', and the ML classifier also flagged it with high confidence. The presence of these links suggests an attempt to lure users to malicious sites, likely as part of a phishing campaign or to download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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 http://eprdel.cz/userfiles/file/xefibaxulovozexig.pdf In PDF document text
    • http://papinchess.ru/userfiles/file/zazolatelutejurikuzijub.pdfIn PDF document text
    • http://childhood-matters.com/clients/49507/File/raxifuxekuloga.pdfIn PDF document text
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c62300ec90f---62441132914.pdfIn PDF document text
    • http://akicgiyim.com/userfiles/file/jofumovezedajomit.pdfIn PDF document text
    • https://uniontend.com/userfiles/files/95844843400.pdfIn PDF document text
    • http://arunimaflavours.com/userfiles/file/31295899667.pdfIn PDF document text
    • https://egyptsuntours.com/userfiles/files/rarowezuv.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/rirojavalonitilakonemob.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609571e57e348---tebobago.pdfIn PDF document text
    • http://www.contal-farmer.com/uploads/files/sadazupe.pdfIn PDF document text
    • http://schokobrunnen.com/idata/jakusufisafujuxesa.pdfIn PDF document text
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/1180c52ad94dcfa358c272e10fffbde5/dosesidox.pdfIn PDF document text
    • http://akkoryazilim.com/userfiles/file/90679857387.pdfIn PDF document text
    • http://ajtoablakcentrum.com/_user/file/kunitoromi.pdfIn PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/27fb8e3f703696b1915b5ced09028dfd/samobadetuxu.pdfIn PDF document text
    • http://africa-emergence2019.com/userfiles/file/45925557955.pdfIn PDF document text
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/39dc85bbf7e706cbf8dc711261c460ca/54039964880.pdfIn PDF document text
    • http://www.franklinwebdesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e20e3db00c---venabomaxutigamifara.pdfIn PDF document text
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607da17401362---11356710932.pdfIn PDF document text
    • https://grupo-bahia-real-estate.com/ckfinder/userfiles/files/40245246032.pdfIn PDF document text
    • https://thefencedocumentary.com/adminfiles/file/83390308973.pdfIn PDF document text
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160817f8f24bc5---61196031000.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=rotisserie+chicken+pot+pie+with+puff+pastryPDF link annotation
    • 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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ef0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF0D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010724.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10724 10968 bytes
SHA-256: 259c0a0c5a8a6ca7880140cbf03877334414b78ab085412028281e5ba8d90c33
font_02_sfnt_off000120b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120B0 17876 bytes
SHA-256: 9a2d17e11e4665fadf27f6e4d453ebbf9199cb2671fd0493e93ef36ed68ef8f2