Malicious PDF — malware analysis report

Static analysis result for SHA-256 b64631f7510351be…

MALICIOUS

PDF

85.3 KB Created: 2021-09-11 02:08:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a128decf58b58f9996d0c35ff94cbe18 SHA-1: 07d6ee6a425c52f0a0056149f495fd7cb2fd8534 SHA-256: b64631f7510351be2d363599d84255b45bad5849592a7e817c71a6b6065eb5b3
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample contains embedded JavaScript, a common technique for executing malicious code within PDFs. It also features a link farm pointing to multiple distinct hosts, many of which appear to be compromised WordPress sites or disposable hosting, suggesting an attempt to obscure the final destination. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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://chinazzjx.com/d/files/27114407415.pdf
    • http://dulichtantai.com/files/uploaded/files/6516134749.pdf
    • https://oncallanatomist.org/ckfinder/userfiles/files/42863323269.pdf
    • http://harlit.com/ckfinder/userfiles/files/20210906_140145.pdf
    • http://ulv-fogger.es/d/files/73694099576.pdf
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bdce595d8b---87539481944.pdf
    • http://euroambulans.pl/userfiles/file/59062350600.pdf
    • https://patidarpalanpur.com/web/k/main_admin/ckfinder/userfiles/files/47808246614.pdf
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/0b239d9b9381a08e376974f9ec6f2435/83316504574.pdf
    • http://www.egavilanes.com/ckfinder/userfiles/files/31024319131.pdf
    • http://vekosgroup.ru/userfiles/file/xosinaxolubofujifi.pdf
    • http://planet-for-events.de/userfiles/file/15623007128.pdf
    • https://kidneystonetreatment.in/userfiles/files/59238107395.pdf
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/0760c1bdb0484dbbd2adc049202d6b87/72382428668.pdf
    • http://tbeaindia.com/userfiles/file/22522563934.pdf
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131dc0293b2d---topugozute.pdf
    • http://demkapi.com/resimler/files/pazetimawopateveg.pdf
    • http://kkc1.org/htdocs/cljr/data/files/88417419781.pdf
    • http://www.integra-cr.cz/administrace/ckfinder/userfiles/files/jibawobaxati.pdf
    • https://www.grandiosa.is/wp-content/plugins/super-forms/uploads/php/files/7ef21p5kud199v31kt2kudkka6/40613907733.pdf
    • http://irpuyesh.com/cache/fck_files/file/84670157517.pdf
    • https://chachachat.info/js/ckfinder/userfiles/files/51402538849.pdf
    • http://studioingegneramato.com/userfiles/files/75255379210.pdf
    • http://geometramaurotozzi.it/userfiles/files/jajetalavofonaneger.pdf
    • http://feynburg-uhren.de/uploads/bimunabaf.pdf
    • http://playbabydoll.com/userfiles/file/91706325906.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=chawl+house+full+episode+watch+online
    • 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_off0000e58f.bin
119843f36eea17f085efdefccd0f87661e08016ef994a891ef7d89dc031e3191
pdf-font-stream PDF embedded font (sfnt) at offset 0xE58F 19048 bytes
font_01_sfnt_off00011637.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11637 16792 bytes
font_02_sfnt_off00012e4e.bin
01e214bbef8af6227b6c69b771b94e5ff4457b3f96a2adf7a5f39ad6c2fd63f5
pdf-font-stream PDF embedded font (sfnt) at offset 0x12E4E 10836 bytes