Malicious PDF — malware analysis report

Static analysis result for SHA-256 ecdf1ae250f94be4…

MALICIOUS

PDF

71.0 KB Created: 2021-07-13 18:49:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 488cf774b990ddacb014763cf7091b48 SHA-1: 57d14d4c4c1b7c6f0b7e37f9bcd6702293cf75d4 SHA-256: ecdf1ae250f94be41b1560931a52ea7ddbd7c43ff419bf6415aaecdcb4015586
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. It contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, further obscuring its true intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://ipcare.nl/wp-content/plugins/super-forms/uploads/php/files/keuf7vfdf60ba9o5rq27hlsqsd/75344573190.pdf
    • http://kahounova.cz/userfiles/file/lagonikawezoxenobex.pdf
    • http://ekachaiguitarist.com/ckfinder/userfiles/files/pevikiro.pdf
    • https://www.heracles-hotel.eu/wp-content/plugins/super-forms/uploads/php/files/18ruo25eithjjk33g8de7h4fmb/niwivuwa.pdf
    • https://amatnieks.lv/pictures/image/durisabij.pdf
    • https://baxsporthorses.com/userfiles/file/xekijomarov.pdf
    • https://juvelyrikoscentras.lt/Files/file/25691197343.pdf
    • http://yanartekstil.com/firma/files/62542511648.pdf
    • https://purpleleafestatebuyers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160807b35289e3---bobusejutuxelap.pdf
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a10b4405e4b---nasekikav.pdf
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/160748c6aeb373---jenisaruwamafuvodazeparit.pdf
    • http://svenstavik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fcf60c35fa---35135216960.pdf
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a08264b1d36---gitikevomevapenovaxoxi.pdf
    • http://studioriboldi.eu/userfiles/files/37429932221.pdf
    • https://vuaship.com/wp-content/plugins/super-forms/uploads/php/files/hvbvr64dd7ooodt6f90s4k348n/76351869124.pdf
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad0e9b25c36---jejumabumewomo.pdf
    • http://a2itsolutions.com/chop/multimedia/userfiles/file/85059996028.pdf
    • http://assistance.uz/images/shared/file/34279300270.pdf
    • https://www.kadinlarsitesi.org/wp-content/plugins/formcraft/file-upload/server/content/files/160881ceb986ec---vowoputefetanikufi.pdf
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca34702ead---giledarinijuj.pdf
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/160baf1c911838---luvumixuxifi.pdf
    • https://takeorders.online/wp-content/plugins/super-forms/uploads/php/files/ht811o2m8vk9h9u345dlah8c8s/sokisijetuzedamarulixi.pdf
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a714e24b04b---94282180260.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=for+loop+for+list+in+java
    • 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_off0000b5ef.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB5EF 16792 bytes
font_01_sfnt_off0000ce01.bin
7f52028402235c664d8e746f0be6fefee942b667ff7ac04bf81af194976bdcab
pdf-font-stream PDF embedded font (sfnt) at offset 0xCE01 15800 bytes
font_02_sfnt_off0000f6e9.bin
4592ba785e642095388a57fc19f13433f3c353a4e5d6c4e2b789ed3e4d17a160
pdf-font-stream PDF embedded font (sfnt) at offset 0xF6E9 10392 bytes