Malicious PDF — malware analysis report

Static analysis result for SHA-256 84976bcc268a7355…

MALICIOUS

PDF

77.3 KB Created: 2021-09-22 17:38:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d28fb1b56867ea9e1f00e04e3c2ae1a3 SHA-1: 39642ba7b61dde3e15ca9210bd46f726cbeec1ef SHA-256: 84976bcc268a7355520bb4cbc19e58a9938a494e77330b861af14009e2d7a55d
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple links to external websites, many of which are hosted on compromised or disposable domains, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the presence of PDF_RANDOM_URL_LINK and PDF_SEO_DISPOSABLE_LINK_FARM heuristics points to the document's role in directing users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://tsg-vaganovskoe.ru/ckfinder/userfiles/files/41460205138.pdf
    • http://www.findvoters.com/userfiles/file/zezuwurovisasawele.pdf
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/7sb099a5s59mbm01eihpbv5i5d/duruponuvota.pdf
    • http://fst-uinsu.net/userfiles/files/pekukimoposadurube.pdf
    • http://originalcheck.it/public/img_admin/file///66924013860.pdf
    • http://arcenevents.nl/site/upload/files/29800906899.pdf
    • http://personnelstrategies.net/userfiles/file/wigipuxibolizipojizenejis.pdf
    • http://mweb.cz/images/file/34063377788.pdf
    • http://soleilboo.com/images/uploads/files/fililomupabisumofosikobot.pdf
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613d5c71135d1---97557246677.pdf
    • http://ambulatorioveterinariopisillibertozzi.eu/userfiles/files/55463806571.pdf
    • http://kaztelcom.kz/ckfinder/userfiles/files/xajuri.pdf
    • https://mackbeks.com/files/file/pibimuxalibog.pdf
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/6a839toavrqfmcgkac5n3k1m14/kemekugoweganonegawe.pdf
    • https://aordonez.com/images/contenidos/files/dosejokugonelepazeg.pdf
    • https://yantrasearch.com/ckfinder/userfiles/files/fovajonebemenubefizemeb.pdf
    • https://watosaphotography.com/app/webroot/userfiles/files/20210908_224655.pdf
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/fsq4oia76vb026v5vfus6e4ros/takuvaziwepufo.pdf
    • http://sentai.cc/data/file/20210909_001002_713.pdf
    • https://slicktechproducts.com/newerac2c/userfiles/file/ridebatibofodalipezo.pdf
    • http://abwninemile.com/uploads/files/sufebaku.pdf
    • http://dekogard.net/deko/veri/_files/degubawuviwepubumibi.pdf
    • http://mdsalon.ru/img/lib/file/nimixatuvubor.pdf
    • http://bidwoodmachine.com/d/files/65322865879.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=complex+variables+spiegel
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c86b.bin
2dff724ad82f658331b0b5c5d5467e19566e22c497e7ed8b52704ac4ffaf7b1d
pdf-font-stream PDF embedded font (sfnt) at offset 0xC86B 17820 bytes
font_01_sfnt_off0000f6f0.bin
18607ab723ba454eec079af6530c0f05e01e16c9a003d09074b077973e9ad255
pdf-font-stream PDF embedded font (sfnt) at offset 0xF6F0 10732 bytes
font_02_sfnt_off00010f6a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F6A 16792 bytes