Malicious PDF — malware analysis report

Static analysis result for SHA-256 6637c5cc0dd056a8…

MALICIOUS

PDF

80.2 KB Created: 2021-08-10 03:45:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-24
MD5: 76f6bf9da690b48a2d8e730aac81c973 SHA-1: afd4eb82e058f350368141002b222fc263a988c8 SHA-256: 6637c5cc0dd056a81a38182278942a69ab0460fa06ba1e792cd1996dddac6ec9
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier suspicious score 0.3497

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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
  • 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.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c05f2f3212e---26158346708.pdf In PDF document text
    • https://maturana.cl/upload/file/65374146876.pdfIn PDF document text
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/160f6fb7814e9b---54073527916.pdfIn PDF document text
    • http://mamtomchabahai.com/uploads/files/files/96321898410.pdfIn PDF document text
    • http://hzqzg.com/d/files/fozujib.pdfIn PDF document text
    • http://ambulatorioveterinarioscapindandrea.it/userfiles/files/12943513680.pdfIn PDF document text
    • http://888chji.com/userfiles/files/24539540032.pdfIn PDF document text
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/0dcc997087dbbe6a15c3bddfccb8c67b/perisugi.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/5420917588.pdfIn PDF document text
    • http://dga.gr/ILC/img/file/ruxolitinana.pdfIn PDF document text
    • https://www.visitrwanda.com/wp-content/plugins/super-forms/uploads/php/files/1470171bcf3cecb053b7ddbad3d28cab/13224737310.pdfIn PDF document text
    • http://benrassam.com/uploads/files/luzipogesusepaxiruz.pdfIn PDF document text
    • http://2ds-creations.fr/userfiles/file/42722155277.pdfIn PDF document text
    • https://civilkontroll.hu/uploads/file/55687183100.pdfIn PDF document text
    • https://amursvoidom.ru/media/files/xuronibeluvosazalur.pdfIn PDF document text
    • https://ruxthai-guesthouse-chiangmai.com/ckfinder/userfiles/files/89004215104.pdfIn PDF document text
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/bdf503906908217a81af623cf4199699/luweda.pdfIn PDF document text
    • http://tt-ural.su/admin/ckfinder/userfiles/files/kunedovidemomene.pdfIn PDF document text
    • http://www.holderit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160858279f0958---46648373477.pdfIn PDF document text
    • https://amerismithenterprises.com/wp-content/plugins/super-forms/uploads/php/files/58e859480de8b51bd514997e44bd39b1/fejuxokovoxonigoraji.pdfIn PDF document text
    • https://promocionesnma.com/wp-content/plugins/super-forms/uploads/php/files/cfa8e54fd9c136bf92d0329bcc8a594e/vomopevomir.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/vcu6k4cb9p43abs7hbgljnc681/kinukipopijojipep.pdfIn PDF document text
    • http://aiken7050.com/clients/5/51/510ae66c864a6d23552e02d1b5190e2c/File/fumepagapakafov.pdfIn PDF document text
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7cbe14d9ee---fipusufep.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=here+comes+the+sun+piano+sheet+music+%28easy+free%29PDF link annotation
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e9ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9EF 16904 bytes
SHA-256: 24649936bbf2a5cc29b329aa4c72ca0b113a9a8d67d05b7e4784d570df0914fb
font_01_sfnt_off00011636.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11636 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1