Malicious PDF — malware analysis report

Static analysis result for SHA-256 f71182852eea941d…

MALICIOUS

PDF

97.3 KB Created: 2021-07-21 12:01:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: f27e73cc2bd37b456ec28970d80aba6c SHA-1: ec420bc814e18b1f0f5651656280bb1b240ae05a SHA-256: f71182852eea941dcde9891b328d73dbe42eec89f0abfa95173567bf16258a07
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 a link farm with numerous URLs pointing to compromised CMS uploads, suggesting an attempt to lure users to malicious content. The document body is heavily obfuscated and appears to be non-readable content generated by wkhtmltopdf.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

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.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160739f3c08c25---59953252699.pdf In PDF document text
    • http://worthingtonpark101.com/userimages/69580538380.pdfIn PDF document text
    • https://sckprime.com/wp-content/plugins/super-forms/uploads/php/files/e7e70732156491f49376c6f9b68a858b/zemufexaki.pdfIn PDF document text
    • http://ctkupavna.ru/upload/file/36852767172.pdfIn PDF document text
    • http://kadh.kr/bobod/upload/file/gepukuziloxezodif.pdfIn PDF document text
    • http://yogo110.com/userfiles/file/linitow.pdfIn PDF document text
    • http://zap-interactive.com/uploads/files/roxiwege.pdfIn PDF document text
    • http://bahattinburyan.com/userfiles/file/vomolajiwalotogasodovipe.pdfIn PDF document text
    • https://bayardplaza.co.uk/wp-content/plugins/super-forms/uploads/php/files/4cu65sbhl91hmn54v88qu965bk/69927126096.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/16089a50aa209f---24298742200.pdfIn PDF document text
    • https://www.prowallpanama.com/wp-content/plugins/super-forms/uploads/php/files/c4d25fe5c87efe20db5300f9b1daa0c3/bibunoradig.pdfIn PDF document text
    • https://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160a19bf1a4710---98111380514.pdfIn PDF document text
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/92df7b2d194a8eb10308cd12f7a56057/10803998208.pdfIn PDF document text
    • http://naszymsladem.pl/upload/file/xowimenu.pdfIn PDF document text
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b2cbb2d4f41---zamuwizogukowowev.pdfIn PDF document text
    • https://www.waterlooarmsnewforest.co.uk/wp-content/plugins/super-forms/uploads/php/files/67c9c4cc5bfdbebfb4bd29ff2a284b6b/69116076818.pdfIn PDF document text
    • https://webtraffic.ch/wp-content/plugins/super-forms/uploads/php/files/bmi9cph76d6u7etj5ee212qvfb/91950067708.pdfIn PDF document text
    • https://www.ideaklinikbakirkoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160800bb562f4f---83827858712.pdfIn PDF document text
    • https://www.accidentinjurylascruces.com/wp-content/plugins/super-forms/uploads/php/files/ithbfn27udvafcv9do2jcno9pa/48045821766.pdfIn PDF document text
    • http://www.mearesandassociatesllc.com/siteuploads/editorimg/file/ruxafujigunimerodujazozol.pdfIn PDF document text
    • https://sip7.pl/autoinstalator/sip7.online/wp-content/plugins/super-forms/uploads/php/files/65e69631b1976c7cbfe8d176b1cfe61b/dusugafavagugu.pdfIn PDF document text
    • https://digidatadecolombia.com/wp-content/plugins/super-forms/uploads/php/files/fc9dbad040859e0c1d04e6a51a861c60/dofevawodebofa.pdfIn PDF document text
    • https://inclinedigital.com/wp-content/plugins/formcraft/file-upload/server/content/files/160712b5058818---53259510369.pdfIn PDF document text
    • https://antoinepanau.com/wp-content/plugins/super-forms/uploads/php/files/abbe3bb362dcb4f2cc88ef97880c09fa/27901712071.pdfIn PDF document text
    • http://epsilonsigorta.com/files/202697777.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088ae3e3888d---4787539263.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=mills+and+boon+romance+novels+free+download+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_off000117e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117E0 17596 bytes
SHA-256: ffa7ccab8c27fd7c3eefcdbf885f6e5a6d0f6552e9e95907d59e8a4a4008d912
font_01_sfnt_off00014659.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14659 10968 bytes
SHA-256: 80e29ed9e2c7224bbc7b20d98c18ec9b44eac305bf82a51e42f916a08279ae59
font_02_sfnt_off00015f98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15F98 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1