Malicious PDF — malware analysis report

Static analysis result for SHA-256 b2253f6f35836ee8…

MALICIOUS

PDF

79.6 KB Created: 2021-09-19 02:57:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0e8c0ccba11cd960b6a58f4295b5f038 SHA-1: 04a4054cf27459583afaeca61ce8bda61a740927 SHA-256: b2253f6f35836ee8626b3ca1cddc26686dd8f9ee74bfc22deef4a0f6048de1ed
204 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF document was flagged by a machine learning classifier and ClamAV as malicious, exhibiting characteristics of a phishing or trojan delivery mechanism. The presence of a fake CAPTCHA lure strongly suggests an attempt to trick the user into interacting with malicious links. Several URLs extracted from the document point to compromised CMS uploads and link farms, indicating a distribution network for malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Fake CAPTCHA / human verification prompt high SE_FAKE_CAPTCHA
    Document displays a fake CAPTCHA or human-verification prompt — used to trick users into running commands or pressing keyboard shortcuts
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ea0027d161---87521950353.pdf
    • http://sotel-perm.ru/site/file/84458477920.pdf
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/2tbt2gpdapgt1gokrbjejuj3nr/2492246190.pdf
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132134363f68---18038114631.pdf
    • http://retrofotr.cz/files/file/gewuruwuxujegozivorude.pdf
    • http://dermatologomiguelgallego.com/miguel/fck/file/19515773715.pdf
    • https://namkhoasaigon.vn/web/images/files/1295613900.pdf
    • http://www.mbk-montage.nl/ckfinder/userfiles/files/23300727031.pdf
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/botoder.pdf
    • http://chip-chup.hu/upload/file/76085935092.pdf
    • http://tzoetemondje.be/uploads/files/wewumegulojagikes.pdf
    • http://violetstudio.in/userfiles/file/93497227320.pdf
    • https://xtremefitness.com.au/application/third_party/ckfinder/userfiles/files/23596049601.pdf
    • https://heart-calligraphy.com/uploads/files/202109031650375850.pdf
    • http://lammermoor.net/imagenes/file/60823368685.pdf
    • http://artpolyclinic.com/file/files/44236377521.pdf
    • http://lesmashclub.com/imgUpload/files/20258875969.pdf
    • https://malabarmail.com/ckfinder/userfiles/files/25664555470.pdf
    • http://www.bargiel.com.pl/ckfinder/userfiles/files/18837346723.pdf
    • http://zkmeiqi.com/admin/ckfinder/upfile/files/74722785983.pdf
    • http://1utilaje.ro/mm/file/didutewudi.pdf
    • http://finsura-lifedirect.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16134cea3cf059---bezilorugasat.pdf
    • http://simoncaulkin.com/images/77081231716.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=google+account+manager+6.0+frp+bypass
    • 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_off0000cf6d.bin
82d91775a74e371f15ae57e509b07d90a0d585f10596ef96ecb580f51208efc4
pdf-font-stream PDF embedded font (sfnt) at offset 0xCF6D 11480 bytes
font_01_sfnt_off0000ea7b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA7B 16792 bytes
font_02_sfnt_off0001028d.bin
92c3e81a96c5015ae0ed304a3c882645211cece95837d49b3d192e2326616296
pdf-font-stream PDF embedded font (sfnt) at offset 0x1028D 17940 bytes