Malicious PDF — malware analysis report

Static analysis result for SHA-256 17a88225683a8167…

MALICIOUS

PDF

69.5 KB Created: 2021-09-28 22:56:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d186eec102f97fcd4c84eb1a7a61a13f SHA-1: 40ea500093e2815b57281313f65fc2abe615f629 SHA-256: 17a88225683a81678fe9a3f87debfdfa27ef50d806a967e07f5ac8528b498be7
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for executing malicious code. It also features a link farm pointing to multiple distinct hosts, some of which appear to be compromised CMS uploads, suggesting an attempt to redirect users to malicious or phishing content. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://nifaelectronics.com/userfiles/file/63403998337.pdf
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/og6rdon9ol074rek5tmkfn6ci2/xafejavare.pdf
    • https://spandoekland.nl/userfiles/file/63416045863.pdf
    • https://rdw-wolf.de/backend/ckfinder/userfiles/files/94087893201.pdf
    • https://geneticapanama.com/userfiles/file/36568124286.pdf
    • http://colleges-in-tamilnadu.com/FCKeditor/userfiles/file/24233828814.pdf
    • http://blgjad.com/upload/files/29261752349.pdf
    • https://chinatupai.com/web/js/ckfinder/userfiles/files/79131563799.pdf
    • http://centrons.com/uploaded/file/3657596886139f86b4ead5.pdf
    • http://belly.bpv.su/content/files/files/24211394691.pdf
    • http://centonze-vini.com/userfiles/files/40204636385.pdf
    • https://kristaldicarlo.com/userfiles/file/87402567300.pdf
    • http://jedzenie365.pl/ckfinder/userfiles/files/68065025897.pdf
    • http://www.gradur.ba/wp-content/plugins/formcraft/file-upload/server/content/files/1614231516cf4d---rajixowotewopizajufutu.pdf
    • http://lnianemarzenie.pl/userfiles/file/dulikabibigujep.pdf
    • https://bf-pomosch.ru/wp-content/plugins/super-forms/uploads/php/files/748dvvf2a8gpetvrqm68gd1856/vedugodasemawofikibil.pdf
    • http://oembag.com/uploads/files/202109190412153293.pdf
    • https://simplehome.ro/ckfinder/userfiles/files/55557921300.pdf
    • http://sooam.com/files/fckeditor/file/8494054646151cf7bcfad8.pdf
    • http://abcbyspu.net/ckfinder/images_store/files/55349577411.pdf
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136f39489f96---gubawitijeborusanibisuxi.pdf
    • http://signexpowholesale.com/project-new/christianbook/upload_images/file/werofamiwudixujuzevuriko.pdf
    • http://acecaalcoy.com/userfiles/file/70817988455.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=the+circle+us+season+2+watch+online+free
    • 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_off0000b211.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB211 16792 bytes
font_01_sfnt_off0000ca23.bin
e0a8112acecf96a0f63f3d66e5e53c0bfd19f4bd0ac36647eef85e3f468db755
pdf-font-stream PDF embedded font (sfnt) at offset 0xCA23 14720 bytes
font_02_sfnt_off0000ef11.bin
09052568964b3ae1589af0fa18b405a0d4eaafa69593a4eece559e75468a5ab2
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF11 10704 bytes