Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a5446a50b7911d7…

MALICIOUS

PDF

79.2 KB Created: 2021-08-06 07:33:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 1127f69f299c9b0f6170044f489d50bc SHA-1: 579e65e63c9ec764d3efcd05e78aab2ac406b530 SHA-256: 3a5446a50b7911d706fbfc52cdeda54249d0e3ae8784eaaca39aeec28afd39ab
156 Risk Score

Malware Insights

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

The sample is a PDF file identified as malicious by ClamAV and an ML classifier. It contains numerous URLs pointing to compromised WordPress sites, which in turn host other PDF files. This indicates a link farm designed to obscure the ultimate destination, likely a phishing page or malware download. No scripts were extracted, but the structure and URL patterns are strongly indicative of a phishing or credential harvesting campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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://oniceh.ru/uplcv?utm_term=public+speaking+handbook+5th+edition+ebook PDF link annotation
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/f1486ddc6d05c4f8ad694ece77abd5ba/64456011125.pdfIn PDF document text
    • https://portsidestrategies.com/wp-content/plugins/super-forms/uploads/php/files/4c3bc763458351faae82fe2464c6dc0a/lutotiropaditarafidus.pdfIn PDF document text
    • http://patp1ryb.ru/media/file/94034069494.pdfIn PDF document text
    • http://alianzablue.com/aym_image/files/28079396383.pdfIn PDF document text
    • http://airbaankhubon.com/userfiles/file/81129013266.pdfIn PDF document text
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/16104bf9fe9a4d---62302078005.pdfIn PDF document text
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/1606f94ff6992c---43099330716.pdfIn PDF document text
    • http://conganbacgiang.vn/app/webroot/uploads/files/wowarizivates.pdfIn PDF document text
    • http://sity-luxe.ru/userfiles/file/89117380337.pdfIn PDF document text
    • http://rsst77.ru/upload/files/57062067643.pdfIn PDF document text
    • http://bawaconstructions.com/editorData/file/jatul.pdfIn PDF document text
    • https://bliznacite.com/files/xeguw.pdfIn PDF document text
    • http://alliance-ltd.com/userfiles/nifudiduvonuwewakuvibab.pdfIn PDF document text
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd72ca20954---45325855722.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/160769f79d7fe5---8461850071.pdfIn PDF document text
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084291de78a1---pikubamufesejedo.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a6469d5924a---28736916780.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c6cd89ddee---jekumexinopafapelawosog.pdfIn PDF document text
    • http://kameleonhastanc.hu/files/file/zepavefixupamakamibiwusuk.pdfIn PDF document text
    • https://rachelrom.com/rescontent/file/labulene.pdfIn PDF document text
    • https://cortopolis.ar/userfiles/file/baxosabure.pdfIn PDF document text
    • https://beautyreviveshop.com/newerac2c/userfiles/file/jefobapase.pdfIn PDF document text
    • http://abnicum.com/files/file/tegedava.pdfIn PDF document text
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/jt9mf083e01ba0c0v5agsd0edl/53157509875.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c5f6ba7b521---23341912023.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_off0000d1a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1A3 16388 bytes
SHA-256: 3d65dd77d1066c3a610977c178176c0f3d080fe74e3f0340432906036bfe081c
font_01_sfnt_off0000fc2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC2D 11160 bytes
SHA-256: d420d2b87d1e908a067ab65787db720a05c5bde6f11233ca74b1aa4425d184de
font_02_sfnt_off000115d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115D6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1