Malicious PDF — malware analysis report

Static analysis result for SHA-256 d426cc8a91adf96e…

MALICIOUS

PDF

87.2 KB Created: 2021-07-08 10:01:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 1e4df034825598f87a1a082695bf1306 SHA-1: 6daf5c73d88440454f247c63a4e820da5f3d18c8 SHA-256: d426cc8a91adf96eccca977d7ff3301422bd3aa749ced3c3480989a223123667
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of multiple distinct hosts and the use of UTM parameters in some URLs further support the link farm and potential redirection strategy.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://laborke.ru/uplcv?utm_term=mexican+dips+for+tortilla+chips PDF link annotation
    • http://backupcenters.com/userfiles/file/gufinewinije.pdfIn PDF document text
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c1219d14f71---febigixe.pdfIn PDF document text
    • https://apotekatia.ba/fajlovi/doxepabaki.pdfIn PDF document text
    • http://hodori247.com/uploads/files/27931921100.pdfIn PDF document text
    • https://palet-school.com/files/files/redizojexel.pdfIn PDF document text
    • http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c52ac699483---vobaxitipusane.pdfIn PDF document text
    • http://szyldkj.com/luodan/images/userfiles/file/52967843186.pdfIn PDF document text
    • http://aapltd.net/userfiles/file/14374871103.pdfIn PDF document text
    • http://www.psoealora.es/ckfinder/userfiles/files/rerasuzagavabezomakep.pdfIn PDF document text
    • http://www.gradur.ba/wp-content/plugins/formcraft/file-upload/server/content/files/160a0dcc63b3d1---warizo.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607d9ac40da88---dizuvaxu.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b9b8172376e---54499854907.pdfIn PDF document text
    • https://gencshoworganizasyon.com/upload/ckfinder/files/35728367971.pdfIn PDF document text
    • http://casaatlantida.com/userfiles/file///89810700827.pdfIn PDF document text
    • http://dulichgiahy.com/upload/file/rixovasagezexadisap.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/f872dc2a4ea28edb094646ca4c8bd4d4/rotuk.pdfIn PDF document text
    • https://icbacademy.com/upload/files/wolosujivejedaki.pdfIn PDF document text
    • http://furkansigorta.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1607cd5b0b675a---57283986352.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608402d6e03da---74467345163.pdfIn PDF document text
    • https://gagiongvitgiong.com/ckfinder/userfiles/files/72502468153.pdfIn PDF document text
    • http://www.anclupnapoli.it/userfiles/file/19364500024.pdfIn PDF document text
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085267fcfef2---434787652.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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f210.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF210 17192 bytes
SHA-256: d98d94f62e4d61d9ad12dbf1f5540bac54d3e76877d159f528b5e101cd88c5b3
font_01_sfnt_off00011ebe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EBE 10812 bytes
SHA-256: d9ad21cf9684e5107409300c2039a20a84b14e9c3c0979193e923aefd0db06f0
font_02_sfnt_off000137a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x137A5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1