Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8b76753c84d7d5c…

MALICIOUS

PDF

70.0 KB Created: 2021-09-26 23:22:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 950eb417d2d23ba0470ba32b0cafe08e SHA-1: bf36035c019955918c3f2678f936bedb5e33d42c SHA-256: b8b76753c84d7d5cf6ef2a702f454b3cba6c84bc8ee8f704a6d0046a6c566c96
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting an attempt to distribute malicious content or phish users. The presence of external URI links further supports the attack pattern of luring users to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/16148f724657df---88792213982.pdf
    • https://www.tyrtaios.gr/ckfinder/userfiles/files/55620135854.pdf
    • https://408of53crownstreet.com/assets/media/files/35721129636.pdf
    • https://dentinale.eu/wp-content/plugins/super-forms/uploads/php/files/a64598e402171b20d91d86ed3887ab7f/1900649225.pdf
    • http://www.polni.si/Images/files/34147634567.pdf
    • https://businessincasey.com.au/application/third_party/ckfinder/userfiles/files/tifenobojijexajamo.pdf
    • https://albizy.com/ckfinder/userfiles/files/geromotaborapuzav.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161369ba67326d---jipalilosevapom.pdf
    • http://brandiassociati.it/userfiles/file/xejawas.pdf
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/c9341656c4d0871f64c0a19a0d656a18/44935760803.pdf
    • http://yavuzselimvakfi.org/resimler/site/files/zodod.pdf
    • https://evpersoneli.net/ev-personeli/file/72676151021.pdf
    • http://flapboxes.custompackageboxes.com/userfiles/files/ziguvu.pdf
    • http://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/16149a4624b7b0---tuvomerusekavidovixanoze.pdf
    • https://ratodua.com/contents/files/31513898146.pdf
    • http://e-kva.ru/admin/ckfinder/userfiles/files/46934724940.pdf
    • http://uniradioweb.info/userfiles/file/fonijida.pdf
    • https://oklogistic.lv/upload/file/431523772.pdf
    • http://xn--42-jlclgg6a3e.xn--p1ai/userfiles/file/xejero.pdf
    • http://rvhifi.cz/files/file/sujawawubemirepaselefu.pdf
    • http://jarosi.hu/files/file/tazapibutadiwubavup.pdf
    • http://cpils.com/userfiles/file/kimojidosidepi.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=download+just+say+hi+apk
    • 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_off0000af72.bin
2ca2ee376adc13fd94b4dbe053599ad3980233ccde0f8a7b69d51ba955c39c73
pdf-font-stream PDF embedded font (sfnt) at offset 0xAF72 16004 bytes
font_01_sfnt_off0000d7fe.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD7FE 16792 bytes
font_02_sfnt_off0000f015.bin
fccd22ee68fdfc4260f9743ae37e89d506df0eb8524b95564a945e8924422a81
pdf-font-stream PDF embedded font (sfnt) at offset 0xF015 10780 bytes