Malicious PDF — malware analysis report

Static analysis result for SHA-256 41038d05d6b870be…

MALICIOUS

PDF

74.1 KB Created: 2021-09-07 01:49:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 5bbe30fc4d5f21bbe05042c2cae89b7c SHA-1: 434581255ce47ea8b462100769afca2b296e312d SHA-256: 41038d05d6b870be228dd1b9bdba9163bcb2a715928bb389630426bbc7278297
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links pointing to potentially compromised WordPress upload directories and disposable hosting, suggesting a link farm used for phishing or malware distribution. The presence of embedded URLs and the PDF structure itself are indicative of an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://ssaisarang.com/ckfinder/userfiles/files/zasora.pdf In PDF document text
    • http://amako-ra.com/wp-content/plugins/super-forms/uploads/php/files/7ff184d6178473879fdafc23c92b946b/49788415988.pdfIn PDF document text
    • http://zawayakw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d6b082a2ff---13341419123.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/et4sqacoe3sfqkeb23hgrj2tl6/kiwarix.pdfIn PDF document text
    • https://too.kg/wp-content/plugins/super-forms/uploads/php/files/d312c30424d6ace95f8945509cf67cc1/36657394499.pdfIn PDF document text
    • http://mobil-tech.com/files/12069688504.pdfIn PDF document text
    • https://mkting.com.co/wp-content/plugins/super-forms/uploads/php/files/a928b35b65877763f4bb99a426e93893/ripat.pdfIn PDF document text
    • http://skikk.be/app/webroot/files/userfiles/files/36597212963.pdfIn PDF document text
    • http://women-for-marriage.com/ckfinder/userfiles/files/zogajor.pdfIn PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/kvl6kn7ac91j1bipcs5nf8j4ka/42504580100.pdfIn PDF document text
    • https://aartipalette.com/userfiles/file/raxoruteragiwitut.pdfIn PDF document text
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1611321a06d94c---63204921326.pdfIn PDF document text
    • http://werkkledingverkoop.nl/images/docman/files/35876593433.pdfIn PDF document text
    • https://laser-arena.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1609443cbc60f3---nukatemolivobisomenelegas.pdfIn PDF document text
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607037eee9fa0---55334617289.pdfIn PDF document text
    • http://www.zulfugar.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607fd1580200c---mesivunexeriwezodewijan.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/ce50f1e6be55ee08e8b78a17de7e4aab/32018828548.pdfIn PDF document text
    • http://bestbelly.org/content/files/files/zamazufoziju.pdfIn PDF document text
    • http://staropolski.net/Upload/file/zujoluwotefumiwepa.pdfIn PDF document text
    • https://www.helpagesl.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a4d21140de5---gekufedubefokesul.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1609c60ee0a747---tubugurapim.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610e1dd421564---nasugezetipi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=holt+mcdougal+larson+algebra+1+textbook+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_off0000bb6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB6B 11348 bytes
SHA-256: 5c77a600317fff4714f73a117017d8c3fc3522e8e8b34b2364754f189fb2c545
font_01_sfnt_off0000d5c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5C6 17532 bytes
SHA-256: 9342e3b2e9bc15b4068cf1ecde2e1a34882d5e38aeaf63191f7d6c51564c8cf7
font_02_sfnt_off000102ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102AE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1