Malicious PDF — malware analysis report

Static analysis result for SHA-256 1f8aa3e551dcf019…

MALICIOUS

PDF

71.4 KB Created: 2021-09-21 20:37:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 426868fd6f555fab34ebf2a509ce8262 SHA-1: ba46e9930a0f890f29d3659de8a24fed8d47ae0b SHA-256: 1f8aa3e551dcf01930be4b7090457dd8b2b0dd9f065f1657e9389efa25420988
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and unreadable, suggesting it's not intended for direct user interaction but rather to host these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://tutorbolivia.com/userfiles/file/24660565897.pdf
    • http://resumesfromabove.com/userfiles/file/74382139431.pdf
    • http://alteredcompta.com/buddha/ckfinder/userfiles/files/pazamikotatex.pdf
    • http://kbo.pl/ckfinder/userfiles/files/mitovimuz.pdf
    • http://the-bom.kr/upfile/files/35406849295.pdf
    • http://komputerzagrosze.pl/userfiles/file/rowapunifuwemuxarabe.pdf
    • https://qatarsecurityservices.com/public_html/userfiles/file/67008466955.pdf
    • http://aprt1day.ru/file/galilefebalowofaselupa.pdf
    • http://hotelrefah4ter.ir/basefile/hotelrefah4terir/files/90966970283.pdf
    • https://limadelimon.com/images/file/97010077669.pdf
    • https://sma-dfgg.org/site/admin/file/xilebewuvunuwaropep.pdf
    • http://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16141234a92255---66407605967.pdf
    • https://semsaesp.com/ckfinder/userfiles/files/domaga.pdf
    • https://thefencedocumentary.com/adminfiles/file/69473623240.pdf
    • https://preciseenergygroup.com/media/gaxila.pdf
    • http://sosnovgeo.ru/userfiles/file/93474729922.pdf
    • http://ipceurope.be/assets/file/29406277722.pdf
    • http://cy2hand.com/userfiles/vunawubarojeda.pdf
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/22df33460a29f157a67db6c01e23e3ab/46757464693.pdf
    • https://nsck-cykelmotion.dk/userfiles/file/jutedeg.pdf
    • http://ever-pioneer.com/upload/files/51378126232.pdf
    • http://dancephoto.ru/userfiles/files/zojogewimozuvuvuzovu.pdf
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/161387e490cd3e---73426926986.pdf
    • http://www.verneteco.com/ckfinder/userfiles/files/73505206955.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=kissing+booth+road+trip+pdf
    • 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_off0000b805.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB805 16792 bytes
font_01_sfnt_off0000d017.bin
cbb33f1ce02903ad04526b14abb4d95e56fbe0350a33ee666def766acdd3b75a
pdf-font-stream PDF embedded font (sfnt) at offset 0xD017 15576 bytes
font_02_sfnt_off0000f7a7.bin
9aec36effe449b6ce8d4b1a7940a2c1a63bb1de5f0c99b26ecc7fff45e116ca3
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7A7 10732 bytes