Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc373688f5249d17…

MALICIOUS

PDF

94.2 KB Created: 2021-09-05 01:58:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 176fd3660c6c66ca20c3d93c5ea4ced6 SHA-1: b123108a56af86281fe16a300b4c5017d12fd513 SHA-256: dc373688f5249d17cbe3f856e85d261fdc1043e64da3cf9f43f99720fa36707a
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to websites hosted on compromised WordPress installations and disposable hosting, indicating a link farm designed to lure users to potentially malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure itself is the attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

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 http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160c6c6acd7d13---donuxotaveraje.pdf In PDF document text
    • https://wentworthre.com/wp-content/plugins/super-forms/uploads/php/files/0068778a6de81d94c17682480755b79f/lorovijanug.pdfIn PDF document text
    • http://autoscuolapezzano.it/userfiles/files/futinusowigujoron.pdfIn PDF document text
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16116e0cda6a97---80043744521.pdfIn PDF document text
    • https://www.ccps.mx/wp-content/plugins/super-forms/uploads/php/files/be6c7d26980d9ac43e144fc88d59216a/gijasuso.pdfIn PDF document text
    • http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/57e6a4f63a73afe2d1dba42a6191ca8d/62153972031.pdfIn PDF document text
    • http://phutunggiahungoto.com/uploads/files/boriwoxobemi.pdfIn PDF document text
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2ee9909fd6---xepipefalelopenudu.pdfIn PDF document text
    • http://asztalosweb.hu/userfiles/file/25501960883.pdfIn PDF document text
    • http://oprandi.it/userfiles/files/lodatu.pdfIn PDF document text
    • http://alwaysshine.com/fileimage/file/fojobizijipenonaxu.pdfIn PDF document text
    • http://www.medicellbank.com/userfiles/files/bobod.pdfIn PDF document text
    • http://acevina.com/webroot/img/files/3945658415.pdfIn PDF document text
    • https://jollytime.ru/wp-content/plugins/super-forms/uploads/php/files/62644870df83201caf34224528dba1a7/tasopijifuk.pdfIn PDF document text
    • https://saksisan.com/upload/ckfinder/files/68608042082.pdfIn PDF document text
    • http://dom-nenilovo.ru/wp-content/plugins/super-forms/uploads/php/files/233778125bf317a2dd0a87be7b1d1471/6706726588.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/e4bd6c55974c80238c8b80d00c121c8a/84406568429.pdfIn PDF document text
    • http://asupuro.com/user_data/image/file/50590386984.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16071fce46e5d8---664966106.pdfIn PDF document text
    • https://baoholaodong24.com/userfiles/file/dulozevoxi.pdfIn PDF document text
    • http://archerelectricsupply.com/userfiles/file/48119362572.pdfIn PDF document text
    • https://erinmillssmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/crv5i0i0e083cgm20jql2a5uj6/10697729580.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/amprdebpk9o39ooea9kmoukonm/88260885903.pdfIn PDF document text
    • https://www.almuhja.com/ckfinder/userfiles/files/pelumifasudor.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=mingrui+wr30m+watch+manual+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_off00010076.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10076 22004 bytes
SHA-256: fd431fad311a0253cbefa0fc6dd45c246b8af2e08537bdbe0a5393187532f8ba
font_01_sfnt_off0001396d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1396D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00015184.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15184 11120 bytes
SHA-256: a8719911546beb3fc0605a1c8de5a2b12d9ebecfba132bdf77aa29e3f560c18e