Malicious PDF — malware analysis report

Static analysis result for SHA-256 25a9f725544c8239…

MALICIOUS

PDF

82.0 KB Created: 2021-09-08 05:22:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: b615fb611976e7c08283fd8bdc94a13a SHA-1: d8a610416c84f62c71f64626f40845a390b7c8aa SHA-256: 25a9f725544c8239e9d0fc8d02573c8db7a6959fabae3e768b4ed38b96e0a333
104 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised websites or disposable hosting, forming a link farm. The ML classifier strongly indicates maliciousness, and the heuristic firings suggest the PDF is designed to exploit users by directing them to potentially harmful content. No specific malware family could be identified.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 6

  • 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://jxloanchien.com/style/postimage/file/lojolitovumovodizaxisi.pdf In PDF document text
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16098d06130968---malezabaxik.pdfIn PDF document text
    • http://coffee33.ru/archive/file/xelemugejilusiwuj.pdfIn PDF document text
    • http://ksnjl.com/userfiles/files/kogedunegesiwakivewu.pdfIn PDF document text
    • https://zippy-inc.com/app/webroot/userfiles/files/pokix.pdfIn PDF document text
    • http://blfimmobiliare.com/userfiles/files/duxejibitugodiwumep.pdfIn PDF document text
    • https://www.ccps.mx/wp-content/plugins/super-forms/uploads/php/files/3c97c95aab05d5ad22314670827fd096/texuxewojekajobiriz.pdfIn PDF document text
    • https://ncsccalgary.com/userfiles/files/mugakekaxoruluxenove.pdfIn PDF document text
    • https://palcev.ru/userfiles/file/futinuvazikipapodige.pdfIn PDF document text
    • https://inverpalmas.com/aym_image/files/givunur.pdfIn PDF document text
    • http://aggengr.com/uploads/CMS/file/72041870303.pdfIn PDF document text
    • http://cjatkinson.com/userimages/palenixepibibuki.pdfIn PDF document text
    • http://findmealocalpainter.com/insurazon/admin/userfiles/file/fefedevibe.pdfIn PDF document text
    • https://ipssecurityconsultants.com/ckfinder/userfiles/files/41690610136.pdfIn PDF document text
    • http://centralgiving.com/media/userfiles/file/30035326563.pdfIn PDF document text
    • https://gameadvisers.com/js/new/fckeditor/userfiles/file/94795513911.pdfIn PDF document text
    • https://presstone.hu/userfiles/file/xonadizirekizosiw.pdfIn PDF document text
    • http://smenergy.kr/uploaded/file/2442357396116afdc34012.pdfIn PDF document text
    • http://preciz.com/uploads/wysiwyg/files/dofararubolapadutopoxej.pdfIn PDF document text
    • http://liccuza.ro/stiri_files/file/44428011653.pdfIn PDF document text
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/160ae4288a84e0---tekedonevalosavaburuvis.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dc16061132d---62276551733.pdfIn PDF document text
    • http://uhli-janmaria.cz/userfiles/file/sigulozasabis.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=vestax+vrx+2000+manualPDF 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_off0000dae4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAE4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f2fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2FB 10536 bytes
SHA-256: c71c2c6cf2ca03ad2e5918f4f26515b8e390546426dc20a116757d5b1f2225dd
font_02_sfnt_off00010b24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B24 18180 bytes
SHA-256: 7b15be53191163ccae2e7f381ecff484c0d9d68782d71e5a107419f86f0f64fe