Malicious PDF — malware analysis report

Static analysis result for SHA-256 15b37f55d7d657e6…

MALICIOUS

PDF

72.5 KB Created: 2021-09-02 19:46:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: ba545a5eb5b3fb842ac617d86c4309c9 SHA-1: 32849648f792386fb81bd62ae940c907f0204658 SHA-256: 15b37f55d7d657e6bab899c0ff9d621d394790a9d817cab78344318f55c14a37
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress sites and other disposable hosting, indicative of a link farm used for SEO poisoning or phishing. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is heavily obfuscated and unreadable, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9885

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://gbeequestriansurfaces.com/wp-content/plugins/super-forms/uploads/php/files/0btmjhi29ekhqbo7hn2rt3rt0h/51414551741.pdf In PDF document text
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dbcd9d195db---suwatopevetagitelak.pdfIn PDF document text
    • https://b2b-intelligence.it/uploads/file/3040172061.pdfIn PDF document text
    • http://broadgatecapital.com/userfiles/file/bumunoda.pdfIn PDF document text
    • https://www.sensiblemachines.com/ckfinder/core/connector/php/files/78002593568.pdfIn PDF document text
    • http://asfalon.com/__files/file/lomezofolibalibotuxevuw.pdfIn PDF document text
    • http://www.physedu.in/newsite/userfiles/files/94818913301.pdfIn PDF document text
    • http://myconnect-thailand.com/image/upload/File/72322572358.pdfIn PDF document text
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2a27798423---movonuwixesux.pdfIn PDF document text
    • https://www.phuketvillarentalandservices.com/ckfinder/userfiles/files/wemisafosozalusetup.pdfIn PDF document text
    • http://pzhjintai.com/upload/files/dibodivawe.pdfIn PDF document text
    • http://2016.letnifestiwal.pl/ckfinder/userfiles/files/39126370813.pdfIn PDF document text
    • https://nedimgame.com/calisma2/files/uploads/tibatikamewimo.pdfIn PDF document text
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f1ab8bc8dd0---97990465189.pdfIn PDF document text
    • http://sip7.online/wp-content/plugins/super-forms/uploads/php/files/4a93b52c86aea101567479d2238078b9/dalupolapep.pdfIn PDF document text
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/80339380d3340cf595323808336c3904/bejajedinamilojiloz.pdfIn PDF document text
    • http://castrolmintabolt.hu/images/upload/file/dewovenuvagaziridemutuk.pdfIn PDF document text
    • http://hart-metale.pl/gimnazjum/userfiles/file/78775299576.pdfIn PDF document text
    • http://chelseafoodmart.com/uploads/files/todabekupipore.pdfIn PDF document text
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608dbad771f42---10412187487.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/5j6ncmn1sleoasfqki1bfmql7g/99338099588.pdfIn PDF document text
    • http://ratchadatitan.com/UserFiles/File/30393154240.pdfIn PDF document text
    • http://studioego.cz/userfiles/file/66439371936.pdfIn PDF document text
    • http://szakkepzosiklos.hu/upload/file/wikiporidaviwejin.pdfIn PDF document text
    • http://93564497.com/userfiles/xetexu.pdfIn PDF document text
    • https://pensiuneavalentina.ro/app/webroot/file/14733054040.pdfIn PDF document text
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/161107001d00fe---58693014333.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=embedded+operating+system+projects+pdfPDF 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_off0000bb12.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB12 15168 bytes
SHA-256: 5891df45d8e7892c3e4770026c0177e08a071d42d465d676fc56a91825a353cb
font_01_sfnt_off0000e1e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1E4 11284 bytes
SHA-256: a5c8828f54323193cdc5891ca735b3d21643652f3749ad452703e3d6c8040fab
font_02_sfnt_off0000fbf3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBF3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1