Malicious PDF — malware analysis report

Static analysis result for SHA-256 a00f8869cb3c624a…

MALICIOUS

PDF

83.5 KB Created: 2021-07-23 10:17:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 599609024747d45f7a33b2efdd6cbeb2 SHA-1: 06120fc32da275a78525ee5021d3c32e93dcaf6e SHA-256: a00f8869cb3c624a4279723900f6360c16399e2d2f4f0dbcc68fccd77e569e05
156 Risk Score

Malware Insights

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

The PDF contains numerous links to other PDF files hosted on various domains, many of which appear to be disposable or on compromised sites. This structure is characteristic of a link farm used to distribute malicious content or conduct phishing attacks. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://xetaihyundai.net/upload/files/nifosesixu.pdf
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/56ccf7f2ce8dac92e7198f553eb57706/55824617462.pdf
    • http://e-skala.pl/userfiles/file/bokefele.pdf
    • http://nfc.soo.jp/file/jikulovadanevorexoxaxuvol.pdf
    • http://skylineidaho69.com/clients/c/c7/c7306e0a9cc1d421caefa9c307ca601f/File/47875462598.pdf
    • https://www.sanier.pl/wp-content/plugins/super-forms/uploads/php/files/4brcjpt16meuvlj0i54ielnee6/7080438305.pdf
    • http://www.ktgroup.co.uk/ckfinder/userfiles/files/56514325047.pdf
    • http://apsara.ru/userfiles/file/nesapomut.pdf
    • http://dawahcity.com/userfiles/file/26557446528.pdf
    • http://agro-partner.com/Image/files/76735754575.pdf
    • https://eyestech.in/wp-content/plugins/super-forms/uploads/php/files/1k7iknkn8o12tuskshdt48u2j0/32228989655.pdf
    • https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/7d99da24f346bcee8b09574d7f225149/lulomuvukijonew.pdf
    • https://activepymes.com/pub/file/nogotefov.pdf
    • http://shethof.ch/cgi-bin/dynamisch/file/68182289140.pdf
    • http://produccionesproezas.com/clients/2/28/28ea8f13eb032e89cab2838ec144e7af/File/zififav.pdf
    • https://cremyco.com/app/webroot/docs/file/tigisezodigipi.pdf
    • http://gostinica-domodedovo.ru/files/nowesivewomo.pdf
    • http://makingtheturngolf.com/clients/9/92/925d9bae4ecf380f28dbe0e1390c16eb/File/86668139267.pdf
    • https://puertoestereo.com/wp-content/plugins/super-forms/uploads/php/files/hl8fd6k5s78a66kafuo1g5udtk/28695502862.pdf
    • http://vitanova-cattery.com/upload/file/39790816081.pdf
    • http://umffz21.ru/admin/ckfinder/userfiles/files/remenutimajo.pdf
    • https://baodinhsolar.com/wp-content/plugins/super-forms/uploads/php/files/fut0ek0e3m5om2ecut7i75jr1l/74325306316.pdf
    • https://pilotcenter.gr/wp-content/plugins/super-forms/uploads/php/files/e6n0e024i7536thojo656gu76n/bopemafodo.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=4+sided+shape+with+no+right+angles
    • 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_off0000e2b3.bin
e811693549cbb674ab1b0dc47cc96c18e5da20a607f00ffe19c9b08ad5deecd8
pdf-font-stream PDF embedded font (sfnt) at offset 0xE2B3 17032 bytes
font_01_sfnt_off00010f33.bin
134599ad834125cac81852292b0fa0b9453c2f9be501879364eae068b2b2f514
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F33 10736 bytes
font_02_sfnt_off000127ad.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x127AD 16792 bytes