Malicious PDF — malware analysis report

Static analysis result for SHA-256 0857c9df8e2de485…

MALICIOUS

PDF

83.4 KB Created: 2021-09-17 07:54:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 29f1da93b542baaabadd4f0ce8f7c8d3 SHA-1: 8f9004a36cb7d715538a73b64431c38615d79a5e SHA-256: 0857c9df8e2de485fb762269775424b3a13ec274c7471045c8e22e4518fdb819
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. The numerous external URIs, many pointing to compromised CMS uploads, suggest a link farm designed to redirect users to malicious sites. ClamAV detection and ML classification strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614155ecec32f---xurajijanadafe.pdf In PDF document text
    • http://hoitruyengiaocodocvietnam.com/uploads/image/files/14576481447.pdfIn PDF document text
    • https://tahsindincer.com/upload/ckfinder/files/96541332202.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16138398e2e29b---98814537273.pdfIn PDF document text
    • https://shotclock.ca/wp-content/plugins/super-forms/uploads/php/files/e4b716fc576e0b816bb04026b158f5fa/24879112084.pdfIn PDF document text
    • https://enkaotomatikkapi.com/depo/sayfaresim/file/wifetewamemezilum.pdfIn PDF document text
    • http://rockhousemethod.com/ckfinder/userfiles/files/99452765411.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/16131658e05e0b---vulirobomutigatit.pdfIn PDF document text
    • http://fanghsin.com/uploads/files/202109100017496277.pdfIn PDF document text
    • http://mkbeauty.vn/luutru/files/56903547115.pdfIn PDF document text
    • https://barcelonacentremedic.cat/files/galeria/files/17510250327.pdfIn PDF document text
    • http://www.salac.cz/ckfinder/userfiles/files/jubidofe.pdfIn PDF document text
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/16137efed5c7e3---36590308168.pdfIn PDF document text
    • https://apaman.ti-am.jp/js/ckfinder/userfiles/files/mujotugapewutelaxo.pdfIn PDF document text
    • https://nepalihemp.com/ckfinder/userfiles/files/78865162521.pdfIn PDF document text
    • http://zanethompson.com/userfiles/file/tugifawoguxetunux.pdfIn PDF document text
    • http://thuonghieutoancau.vn/uploads/files/54791599973.pdfIn PDF document text
    • https://everestart.com/images/stories/file/49519077198.pdfIn PDF document text
    • https://alemarferries.alemarsnp.gr/ckfinder/userfiles/files/sujefevamemokanazusub.pdfIn PDF document text
    • https://affordans.com/ckfinder/userfiles/files/fizalujipezezowegarepafal.pdfIn PDF document text
    • http://msslink.ru/userfiles/files/6366806801.pdfIn PDF document text
    • http://hanauhrova.cz/files/36327732816.pdfIn PDF document text
    • https://htijsr.com/userfiles/file/vigarisunomisan.pdfIn PDF document text
    • http://traditionsradio.com/wp-content/plugins/super-forms/uploads/php/files/18c8ff43a29a5c3ed2c3056c262c873f/doxonizekikiginelutuxil.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=empire+at+war+trainerPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e0f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0F5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f907.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF907 18604 bytes
SHA-256: 3e8e4ce46ea356c79ff6f38fba77694d7dc0357e4692b2d7b4727ee3586dab20
font_02_sfnt_off000129ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129AE 10148 bytes
SHA-256: 5789bd970f73acbb48ac44a32e24eb89ab538154e7c7c5b80436b78544531cc8