Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb81d9fe6a4aa4c2…

MALICIOUS

PDF

91.1 KB Created: 2021-08-03 21:45:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 7e895b48011907e6b82c527d1c45f248 SHA-1: cace731254948757ecafd39c299e78bab829026f SHA-256: fb81d9fe6a4aa4c2821a4bca88ff09a6c1de8120f624b8f7cfc39a74a546c862
164 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

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

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://portsidestrategies.com/wp-content/plugins/super-forms/uploads/php/files/6d5d17531a19285c402b63a08d7da3f4/86942899081.pdf In PDF document text
    • https://xn--22ck6bdp5cach0mc23a.com/ckfinder/userfiles/files/70396901192.pdfIn PDF document text
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/4347000a2c06abd6b52ba68575a8bb53/78733014862.pdfIn PDF document text
    • http://ligneus.hu/upload/file/kajuwolupiva.pdfIn PDF document text
    • http://preserveproperties.com/userfiles/files/zuvogojufeki.pdfIn PDF document text
    • https://kaxtongroup.com/home5/maxconne/public_html/kaxtongroup/assets/images/newspostimages/files/7535077.pdfIn PDF document text
    • http://facyt.com.ar/ckfinder/userfiles/files/bawasixukejabeneteru.pdfIn PDF document text
    • http://photographybynami.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5bdfbe8f59---96171035255.pdfIn PDF document text
    • https://aihr-iadh.org/uploads/FCK_files/file/56943851837.pdfIn PDF document text
    • https://audreyheselmans.com/_files/file/sorerutuwabomalujoda.pdfIn PDF document text
    • https://prana.video/wp-content/plugins/super-forms/uploads/php/files/ndrqccc3ufsehntqehha4a5qvb/94452481392.pdfIn PDF document text
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/4822092cd6ded023c0cee808694f0ed1/ninudigapotirozarozekij.pdfIn PDF document text
    • http://ithaca1962.com/clients/41687/File/zulusi.pdfIn PDF document text
    • https://www.m2asolutions.com/wp-content/plugins/super-forms/uploads/php/files/a51cff486f57b686e895807a0deb6c95/69021131189.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d9f223b3e34---kilifeputotononuxazu.pdfIn PDF document text
    • http://riskhedgetech.com/uploaded/file/168281053260f3228446890.pdfIn PDF document text
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4bf124adcb---44901907394.pdfIn PDF document text
    • http://chizclean.ru/files/fck/file/21715436952.pdfIn PDF document text
    • http://nedirajtebosnu.net/userfiles/file/66180692321.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094c7fbd0c9d---21695164808.pdfIn PDF document text
    • http://ventiliatoriai.lt/js/ckfinder/userfiles/files/moranirupusuvemoxesofub.pdfIn PDF document text
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2a91fb6d47---19291545448.pdfIn PDF document text
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608086233df05---lonigapowire.pdfIn PDF document text
    • http://canvangdientu.com/images/file/26749056255.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=how+to+weed+infusible+ink+transferPDF 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_off0000fefb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEFB 17540 bytes
SHA-256: 635bc8728d9a87028161a7c0aab3b94e8ba8fce5c0f7e91b30ff7b254a904f3f
font_01_sfnt_off00012d32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D32 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014549.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14549 10756 bytes
SHA-256: 48fe79750b635ec6c7b95d74e1c40d60f56063e52bfc9bb479549e16e56aa705