Malicious PDF — malware analysis report

Static analysis result for SHA-256 b38bbb091f540021…

MALICIOUS

PDF

68.7 KB Created: 2021-08-28 03:20:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 55ea5276e2e70ad97cb345eea9750249 SHA-1: 2f2db515d0920c4d9548562d9ec8fb89a6c7b7d1 SHA-256: b38bbb091f5400213087abd347c014ff7cdc593f08816442273ffced593afcc1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://modra-skola.cz/userfiles/file/togovejuzuterelutiwal.pdf In PDF document text
    • https://contabil-fiscal.ro/mm/file/65658538545.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/160871fbf34d72---8271458306.pdfIn PDF document text
    • http://wdnederland.nl/file/jitepokokeludapodotuba.pdfIn PDF document text
    • https://baongochoa.com/upload/file/lozarise.pdfIn PDF document text
    • http://ecohouse-lab.de/userfiles/file/97358444520.pdfIn PDF document text
    • https://careoncall.in/userfiles/files/12643914529.pdfIn PDF document text
    • http://bioscipublisher.com/files/upfiles/file/tozabegidavufejuvipax.pdfIn PDF document text
    • https://aimtronu.org/userfiles/file/fipulubef.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a85764e4745---14403780641.pdfIn PDF document text
    • http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ac9556887c---85650181401.pdfIn PDF document text
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/5rggc7ibd778m20bsv67t0ugod/vejijufuweri.pdfIn PDF document text
    • http://zulassungsdienst4you.de/bilder/file/73303002756.pdfIn PDF document text
    • http://www.valathors.com/ckfinder/userfiles/files/jironigudeponat.pdfIn PDF document text
    • http://vejwun.cz/images/vuvavebomerazowagawub.pdfIn PDF document text
    • http://www.alex-vasilkov.ru/images/wisdom/file/fubusebipitubula.pdfIn PDF document text
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/f52f1de56fe4ad80359b484caddbfbbd/kesar.pdfIn PDF document text
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc6a335876a---padozale.pdfIn PDF document text
    • http://daehwa.info/uploaded/file/fabiriluwudapul.pdfIn PDF document text
    • http://poney-club-romilly-aigre28.fr/userfiles/file/62025804493.pdfIn PDF document text
    • http://patokapugsnkisses.com/clients/61143/File/45896757442.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=approximation+rules+in+mathematicsPDF 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_off0000ad76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD76 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c588.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC588 15344 bytes
SHA-256: 6c72a687f7b5d9f32ec865411a367f94d92ac91a620636298eb51290db8f041a
font_02_sfnt_off0000ece8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECE8 10824 bytes
SHA-256: a786d6a6d3b7ef2ec0b38241ab978b4fbb31bf051ba7509edee58765f60b7c64