Malicious PDF — malware analysis report

Static analysis result for SHA-256 dff566caaa9ee2a0…

MALICIOUS

PDF

74.3 KB Created: 2021-09-18 19:18:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 074c6f7ba2f1077a94612e1ad3514dc3 SHA-1: 2bce0fca959a348d12ed21d57dc9c1f3dd93430c SHA-256: dff566caaa9ee2a0b27d95ac2340ed86a841e5af50dd67af65ae2ba7c1b5d306
134 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 malicious PDFs. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic and the numerous extracted URLs indicate a link farm, likely intended to redirect users to malicious sites for phishing or scam purposes. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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
  • 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://ilturismoinitalia.it/userfiles/files/73723883550.pdf
    • http://akcompany.vn/uploads/userfiles/file/fisijasidaridopezijag.pdf
    • https://aqua2go.pl/galeria/file/denoxirinemegoze.pdf
    • http://tumwebthailand.com/ckfinder/userfiles/files/26243613176.pdf
    • https://tomclarkvoiceovers.com/userfiles/files/5706938151.pdf
    • https://gitteszoneklinik.dk/ckfinder/userfiles/files/15208110294.pdf
    • http://www.sec-ollivier-associes.fr/www/upload/file/raxipitulibivolu.pdf
    • http://yuanhebiotech.com/upload/files/3463506657.pdf
    • http://huyndaicaudien.com/upload/files/54241412927.pdf
    • https://aneri12.eu/res/file/75374804531.pdf
    • http://arcos-eff.it/userfiles/files/linisaf.pdf
    • https://ykitraders.com/UserFiles/file/29820055863.pdf
    • https://apaman.ti-am.jp/js/ckfinder/userfiles/files/20190037876.pdf
    • http://dwallacelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/38440919796.pdf
    • http://friend5190.xyz/js/ckfinder/userfiles/files/94135160565.pdf
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613082df551f4---gavomirifisisopaket.pdf
    • http://vina2002.com/uploads/files/fogododis.pdf
    • https://maidintown.co.uk/wp-content/plugins/super-forms/uploads/php/files/a2123e51b4f6a0b14df1043eeda20932/52208974987.pdf
    • http://keacg.com/upload/files/lorujumivesaz.pdf
    • http://hasanmasat.com/ckfinder/userfiles/files/roveboselituwex.pdf
    • https://bela.geekers.tw/upload/file_folder/file/fawinus.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=first+name+last+name+chinese+example
    • 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_off0000bc87.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xBC87 16792 bytes
font_01_sfnt_off0000d49e.bin
fabe07facee65267e882c959bb2660f5f2a5656524c2f20ebb45431347298d75
pdf-font-stream PDF embedded font (sfnt) at offset 0xD49E 10600 bytes
font_02_sfnt_off0000ec9c.bin
fc778b6b974bb1948ef3b52ffdb7add2e6a84d4576ef72b8038408197e0c547c
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC9C 18164 bytes