Malicious PDF — malware analysis report

Static analysis result for SHA-256 b07a0f506b2e2342…

MALICIOUS

PDF

76.5 KB Created: 2021-09-11 22:30:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 4c3fc95c49b628c66405c489147e82bf SHA-1: 67a31339ce7d536967c965861f59885f2c164333 SHA-256: b07a0f506b2e23422276ead39768a83414cd83bd8fc2ab725ee520aae46e38e2
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of 'utm_term' parameters in some URLs indicates an attempt to track user engagement with these lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://wsbe17hongkong.hk/_bin/ckfinder/userfiles/files/firiludexisebekav.pdf In PDF document text
    • http://gelinyuanyi.com/upload_fck/file/2021-9-4/20210904145254291219.pdfIn PDF document text
    • https://tourgardan.com/basefile/tourgardancom/files/tafomakosuwuxunebi.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/161323899116d1---pebajun.pdfIn PDF document text
    • https://atkarisuli.hu/userfiles/file/93054420152.pdfIn PDF document text
    • https://lensprovn.com/ckfinder/userfiles/files/samazerifajasamuf.pdfIn PDF document text
    • http://9y.bfage.com/upload/files/20210904201649.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/16138dfea9af07---9090765265.pdfIn PDF document text
    • http://tungalag.mn/userfiles/files/javawo.pdfIn PDF document text
    • http://nutronicltd.com/userfiles/file/joxozibafufipu.pdfIn PDF document text
    • http://omniatel.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613450fc06533---jiwitizonalofikig.pdfIn PDF document text
    • http://midospa.com/upload/files/11435228563.pdfIn PDF document text
    • http://realcomfort.ru/content/upload/file/vedufolofogagewi.pdfIn PDF document text
    • https://eurouniversal.eu/ckfinder/userfiles/files/nuvosilawenefutazapen.pdfIn PDF document text
    • http://www.cheapmotorcycleinsurancepa.com/wp-content/plugins/super-forms/uploads/php/files/bc9100513f8b0a9250138b5dc32769a8/28924074219.pdfIn PDF document text
    • http://farashimirooz.com/files/37366912182.pdfIn PDF document text
    • http://sergeisurzhin.ru/ckfinder/userfiles/files/55330098995.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/63171271097.pdfIn PDF document text
    • https://miguktour.com/FileData/ckfinder/files/20210902_611DAACDEF177D79.pdfIn PDF document text
    • http://goldsunjsc.com/upload/files/dewizis.pdfIn PDF document text
    • http://safiorida.dk/operatori/userfiles/file/41048849471.pdfIn PDF document text
    • https://kibledergisi.net/resimler/files/2496569209.pdfIn PDF document text
    • http://pericosrentcar.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1613bf178b0427---29722397702.pdfIn PDF document text
    • http://learningkey.org/userfiles/bugedo.pdfIn PDF document text
    • http://insei.eu/userfiles/files/68108196489.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=minecraft+mobile+download+apkPDF 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_off0000c6f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6F5 17268 bytes
SHA-256: ba7503affa68469c71afa66fa23d9c1c484a44e0a1a14db04332bc463ad6d5d3
font_01_sfnt_off0000f31e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF31E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010b35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B35 10924 bytes
SHA-256: 741e04e74d2bbc0d7f6c095c9354c24e78b50fca9a30d94c0ba0318319cf8b65