Malicious PDF — malware analysis report

Static analysis result for SHA-256 a40954c28be187ec…

MALICIOUS

PDF

79.0 KB Created: 2021-09-06 12:26:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 802836e0471ec109aa66ad4eaa050dac SHA-1: d42eb4c4e032536a2dd3c6e521ac15f0d5b5b821 SHA-256: a40954c28be187ec86bfee15a44fed05a0127e62fd49e07f8241f06789e6ba3b
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to unknown or potentially compromised domains. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM rules further supports the malicious nature, suggesting an attempt to distribute malicious content or phish users through a network of disposable or compromised websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://mengnuanua.com/app/webroot/files/files/27047232957.pdf In PDF document text
    • https://ntct.dz/ckfinder/userfiles/files/kosowemejavume.pdfIn PDF document text
    • http://cecev.com/stockages/files/rumirujexosavi.pdfIn PDF document text
    • http://cuuhoatudong.com/upload/files/67311296465.pdfIn PDF document text
    • https://birsamundapark.in/userfiles/files/kavumodejipibis.pdfIn PDF document text
    • http://generale-bureautique.fr/gdb/files/file/mulivelovulerakepuba.pdfIn PDF document text
    • https://nmcs.ca/userfiles/files/zekewowud.pdfIn PDF document text
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/7ecba53ff6bff5aac8d5713236f16c38/93580942309.pdfIn PDF document text
    • https://creativitagh.com/pevron/www/img/file/1060147553.pdfIn PDF document text
    • http://anhbanglaw.com/userfiles/file/serebobo.pdfIn PDF document text
    • http://jfe.hk/userfiles/befosepur.pdfIn PDF document text
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612a6e1e459d7---piwowarasulorobup.pdfIn PDF document text
    • http://ranjitabiswas.com/userfiles/files/82810711927.pdfIn PDF document text
    • https://hostessima.pl/userfiles/file/70306881844.pdfIn PDF document text
    • http://henca.com/files/details/file/tigofizarube.pdfIn PDF document text
    • https://www.sixteengrams.com/wp-content/plugins/super-forms/uploads/php/files/e4311ch2t4jvu1qr7cmf7jt05s/48209408065.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c73399b52c3---vevamoguxegesi.pdfIn PDF document text
    • http://ntrc.biz/clients/f/f0/f0759d16aca5b3dfc9163ee994587b7f/File/54614489935.pdfIn PDF document text
    • http://piqiso.ru/userfiles/file/64483645143.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16085363906510---49960165825.pdfIn PDF document text
    • http://kangs78.com/clients/66216/File/ligivonofivivupede.pdfIn PDF document text
    • https://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/997483d5d2caf00acb54e3553826afa1/zemabavogabokod.pdfIn PDF document text
    • http://standdominica.org/files/files/lujiroluzepovagur.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=minicargador+john+deere+320d+manualPDF 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_off0000d13f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD13F 11188 bytes
SHA-256: 71189f4782a76caf6f88176f4435a60620cf971827f291a288b9138aac74aefc
font_01_sfnt_off0000eb01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB01 16604 bytes
SHA-256: b2ebde2cfc22db310bc826b8df8cccea0f481b6d97a89a357c449547777ea77e
font_02_sfnt_off0001161d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1161D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1