Malicious PDF — malware analysis report

Static analysis result for SHA-256 faf90f82c3da7778…

MALICIOUS

PDF

82.5 KB Created: 2021-09-17 08:38:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: c9287c65b931ae9862b6501d66d9ce94 SHA-1: 4bd3038fb462774abeb91a335683085e13279d5b SHA-256: faf90f82c3da77783dfd69ce5c1f1772c36f921d8f5cf221eba71cf0c8514a63
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to distribute further malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. The document body is unreadable, but the heuristic firings and URL analysis are sufficient to infer a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 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://52963566.com/upload/file/202109030219508231.pdf In PDF document text
    • https://promaxsuspension.com/csmimage/file/suzapamodoguseziruma.pdfIn PDF document text
    • https://wecareu.net/ckfinder/userfiles/files/90272588990.pdfIn PDF document text
    • http://chinalabware.ru/d/files/77145322038.pdfIn PDF document text
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/38af92956a9f6d60ca1f8308d03fd57c/kijumopazot.pdfIn PDF document text
    • http://105chers.netsociality.com/upload/files/1024427747.pdfIn PDF document text
    • http://chronocertif.com/userfiles/file/livagoka.pdfIn PDF document text
    • http://inbond-cn.com/userfiles/file/71448857768.pdfIn PDF document text
    • http://namngonviet.com/user-/files/64440122060.pdfIn PDF document text
    • https://synersys.fr/contenu/file/zibifidawexav.pdfIn PDF document text
    • http://joshuadacosta.com/wp-content/plugins/formcraft/file-upload/server/content/files/161333c4a78097---vijib.pdfIn PDF document text
    • http://ansing.nl/userfiles/file/wumirobimepegisezoma.pdfIn PDF document text
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/d42cf711b8096912429e1a0f2b73f3f4/97707103177.pdfIn PDF document text
    • http://handgun.ee/media/file/zifojonolipupa.pdfIn PDF document text
    • https://pilot-nav.socksnbows.com/ckfinder/userfiles/files/20397584877.pdfIn PDF document text
    • http://stoewebdesign.no/userfiles/file/31205631213.pdfIn PDF document text
    • http://vagyonvedelemszolnok.hu/admin/fck_upload/file/sibubejuruzimeseroj.pdfIn PDF document text
    • https://edarky.net/data/file/gemavuwokurogurenapudaka.pdfIn PDF document text
    • http://tearose-kitchen.com/sites/default/files/images/imcefile/gibuduvura.pdfIn PDF document text
    • https://lienlacanien.com/img_pages/file/22167148055.pdfIn PDF document text
    • http://stomerijindex.nl/images/uploads/getexipemegeja.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=download+jhm+tech+frp+unlockerPDF 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_off0000db21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB21 18152 bytes
SHA-256: c052e7c45da57c60dcc49d78424be903f08b383056e73c20f7b07173a6ec82ff
font_01_sfnt_off00010ab8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AB8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000122cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122CF 11036 bytes
SHA-256: 44a97b0887cfc619e10b840162e684fcf436bc4cf5e2b3d5daaf5fcc4c2451b1