Malicious PDF — malware analysis report

Static analysis result for SHA-256 eff59a6e4d450181…

MALICIOUS

PDF

81.4 KB Created: 2021-09-07 20:42:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: a66c47500758d1308beaa91bdbc9e143 SHA-1: d69694066b4dbfefb15c37c7ec5e963720e61eac SHA-256: eff59a6e4d45018179294675c3519ff0d753ca3bd164939c965582ca0f617179
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • 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.
  • 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://xsteelstock.com/d/files/63452714647.pdf In PDF document text
    • http://minuspk.ru/minuspk.ru/userfiles/file/18348924723.pdfIn PDF document text
    • http://foodchemsino.com/d/files/tiguzorabu.pdfIn PDF document text
    • https://vetregistr.com/ckfinder/userfiles/files/vobisutovuxufixomom.pdfIn PDF document text
    • http://agroanaliz.by/upload/editor/files/62244373848.pdfIn PDF document text
    • https://immo-macedo.lu/userfiles/files/girazevofifekix.pdfIn PDF document text
    • http://kompletucetnictvi.cz/files/file/fazopun.pdfIn PDF document text
    • http://e-cluny.cz/UserFiles/file/resonaguwulabax.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ee0c8f8406d---78185324055.pdfIn PDF document text
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/160c13f8e6b1b8---xufokuxufumutedori.pdfIn PDF document text
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607715d39b793---97135611255.pdfIn PDF document text
    • http://skrabl.pl/www/rpbd/fck/file/99416819391.pdfIn PDF document text
    • http://jrpst.pl/userfiles/file/zegodolafiw.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090ee0585133---kekaze.pdfIn PDF document text
    • http://dpholding.ru/uploads/files/37972183627.pdfIn PDF document text
    • http://geostudio.eu/userfiles/files/tejofotugafexunonajo.pdfIn PDF document text
    • https://tigapilar.com/upload/files/gewevemamutosapedesekapa.pdfIn PDF document text
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/d99292ab1889e3c84cf6e70c490a488e/3934857717.pdfIn PDF document text
    • https://fnb-concepts.com/images/uploads/files/35374552101.pdfIn PDF document text
    • https://areicon.com/images/file/roboruwonil.pdfIn PDF document text
    • http://www.yeosung21.or.kr/ckfinder/userfiles/files/1628209736.pdfIn PDF document text
    • http://zelene-centrum.cz/webpagebuilder/ckfinder/userfiles/files/32358776073.pdfIn PDF document text
    • http://clairerolo.com/userfiles/file/68997411041.pdfIn PDF document text
    • https://dolupin.com/calisma2/files/uploads/gafikogo.pdfIn PDF document text
    • http://www.la-rocca.pl/app/webroot/files/files/safibokupolagafezu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=sintomas+de+asma+en+ni%C3%B1os+pdfPDF 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_off0000d729.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD729 18216 bytes
SHA-256: 1dd48b3decdf065c9f1e90e5b5ac53a651e702e05ae32b038159be35aaaf238b
font_01_sfnt_off00010517.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10517 10792 bytes
SHA-256: f1c92ec6abc67b12224366bb99966af9d284f45290af86a67513b3b792d548f4
font_02_sfnt_off00011da8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DA8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1