Malicious PDF — malware analysis report

Static analysis result for SHA-256 b23f8a46ab363263…

MALICIOUS

PDF

92.1 KB Created: 2021-09-05 18:35:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-07
MD5: a632542844b3018219a37419ad7bb699 SHA-1: 6d2fbd2756af53dfd82256af8d82c5c2c4f99d57 SHA-256: b23f8a46ab36326354489b6f6d989b982ce25419feb6893ec9de15fa0146a2ce
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised WordPress sites and disposable domains, indicating a link farm designed to lure users to potentially malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document, possibly delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/krlmvn20ejpp123r8b29df0jr9/vilakosopekab.pdf In PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/db91d6a92de80ce37826fca024cd152e/pemajanewo.pdfIn PDF document text
    • http://hvezda-pardubice.cz/files/file/43690715156.pdfIn PDF document text
    • http://secureyun.cn/uploadfile/file///2021081315441773.pdfIn PDF document text
    • https://yidinfo.net/wp-content/plugins/super-forms/uploads/php/files/ljq6c32hj94bki9gu6k1vu8r30/90018005636.pdfIn PDF document text
    • http://tivati.com/uploads/userfiles/file/lexejagepexow.pdfIn PDF document text
    • http://rexant.by/upload/editor/files/39151464967.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/9p0hdn4uepjp2avbsa8st6uoop/39746674829.pdfIn PDF document text
    • http://www.papelerialapiceros.es/ckfinder/userfiles/files/jopuzuxuve.pdfIn PDF document text
    • http://www.vako.vn/app/webroot/uploads/files/fumijutemesuruxalok.pdfIn PDF document text
    • http://vita24h.com/uploads/userfiles/file/kemedupufisidexofedumodo.pdfIn PDF document text
    • http://iwish-cosmetics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160eca981ee223---refufobenisen.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b3b0374fa8c---90427091901.pdfIn PDF document text
    • http://dothanhigh1970.com/clients/6/63/63ba8bdc6fdca46b25bb56d5732eafc9/File/ronulemebogarupofukoki.pdfIn PDF document text
    • http://www.orarestauratorisaf.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a03906ef45d---nizoditiforumesosalivawi.pdfIn PDF document text
    • https://laurallo.com/ckfinder/userfiles/files/modisas.pdfIn PDF document text
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160af9862a9215---681945112.pdfIn PDF document text
    • http://barcelonasixtytwo.com/userfiles/file/jabezixujidatukuja.pdfIn PDF document text
    • https://4cmedica.com/ficheiros_upload/file/sesetatoberaxufoga.pdfIn PDF document text
    • http://wonsakai.com/uploads/files/zatoveziwemuvevorelareru.pdfIn PDF document text
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16095a0070b2b7---91930989737.pdfIn PDF document text
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096dc1f339b8---jagifedubome.pdfIn PDF document text
    • http://ivankotov.ru/img/lib/file/87494448373.pdfIn PDF document text
    • https://smilepath.com.au/wp-content/plugins/super-forms/uploads/php/files/4dd227f7894f0f8b5adb594f96bec0a1/fubelofomusiketuvuzurole.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=qiagen+dna+extraction+protocol+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_off00010090.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10090 18620 bytes
SHA-256: 8f074f177b517a408c345fba1f2a87cfe58c049b615c3cb64518571c749391d4
font_01_sfnt_off000131cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131CB 10788 bytes
SHA-256: 943c0ddf1ccc3f049989a6dcce8b53cd6bf8d3d33bcee037c46efb37346a5feb
font_02_sfnt_off00014a9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14A9F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1