Malicious PDF — malware analysis report

Static analysis result for SHA-256 be61da14c7e45b9c…

MALICIOUS

PDF

71.4 KB Created: 2021-09-20 09:15:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0cdd9acfe96105dc3b9a23b2914b9cd4 SHA-1: d8d8233af6a67fbb19f0959065cde12f19ca6cb6 SHA-256: be61da14c7e45b9c13ecc0540cbccf8169fff668827a907dfb16458c9c5ae9f9
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to compromised WordPress sites acting as link farms. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates these links are likely used for SEO poisoning or to direct users to malicious content. The presence of multiple compromised CMS upload links further supports the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 https://crewmak.ru/uplcv?utm_term=bakugan+defenders+of+the+core+ds+rom
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/161383711a3897---womudirejapobugiviwe.pdf
    • http://xn--80aaa1acmiejxr6d7fg.xn--p1ai/data/files/mobeleduvudelekud.pdf
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145c8fb36509---nerenujixukurob.pdf
    • http://issaproject.com/app/views/panel/ckfinder/userfiles/files/dedemapu.pdf
    • http://kraemer-duennebacke.de/files/file/rizumedewonugesaboweki.pdf
    • http://www.rify.us/cms-uploads/files/5465870740.pdf
    • https://felicityokolo.com/file/97929236742.pdf
    • http://ventilyatsia-v-sochi.ru/ckfinder/userfiles/files/nigajonozo.pdf
    • https://ibericadearmerias.com/file/9857035704.pdf
    • http://yilbasipromosyonu.com/userfiles/file/verugalodixin.pdf
    • http://grupafurman.pl/!mag2011/userfiles/file/rubobavazoded.pdf
    • https://renesens21.com/ressources/upload/files/17413881078.pdf
    • http://poketomecam.com/uploads/files/9997980317.pdf
    • http://rotarybrescello.it/userfiles/files/87645588255.pdf
    • http://cukiernia.eu/upload/files/41881098436.pdf
    • http://lt101shop.com/userfiles/files/nafikomubupawijolewusal.pdf
    • https://aynispirit.nl/userfiles/file/bifenixifa.pdf
    • http://abacusnancy.com/userfiles/file/julonetomakotazigorurade.pdf
    • https://isosklo.cz/uploads/tiwobuwuzijomajubo.pdf
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/g9032il3e4avlpmdv6okg5hm6f/jadezejunesotulopupev.pdf
    • https://www.tahitotfalu.hu/ckfinder/userfiles/files/gekofukilifezojixe.pdf
    • http://netisiletisim.com/guvennet/resimlerfiles/30741591314.pdf
    • https://cmoretv.com/userfiles/nolowunir.pdf
    • 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_off0000b4e4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB4E4 16792 bytes
font_01_sfnt_off0000ccfb.bin
59a3add095dde7982ad29c9f79fe99c41b023dae02aed1f7ba3b1b070e6ff010
pdf-font-stream PDF embedded font (sfnt) at offset 0xCCFB 11032 bytes
font_02_sfnt_off0000e653.bin
f4eca14e077e58221fa5404d298f91dff5fccdb15d48d9ba9c3f2885b833f84d
pdf-font-stream PDF embedded font (sfnt) at offset 0xE653 16264 bytes