Malicious PDF — malware analysis report

Static analysis result for SHA-256 c3fe24ef0a21fa13…

MALICIOUS

PDF

79.0 KB Created: 2021-09-01 01:06:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1823a5022ce188a641ada6ba1b900bc2 SHA-1: 60573191f5dccbfc5ffb3f02e4c20e18a9cf4957 SHA-256: c3fe24ef0a21fa132394ac3c0d3a61fac80c142008f43cc46a1dff8852d6bc27
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as a link farm, with many URLs pointing to compromised CMS upload directories. The ML classifier and ClamAV also identified it as malicious, specifically as a phishing trojan. The document body is heavily obfuscated and unreadable, but the presence of numerous external links suggests an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073f6ee75186---gifikadux.pdf
    • https://atlastoursntravels.com/userfiles/file/gulabideremufo.pdf
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609834aaae04e---14583885002.pdf
    • http://www.emporiocaritaspisa.it/wordpress/wp-content/plugins/formcraft/file-upload/server/content/files/160934e3603012---vewijukaxoguni.pdf
    • https://pima-alarms.rs/slicice/file/68659606244.pdf
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/17396ac1a80518c6d0348ce6588cbf7a/bewanerol.pdf
    • http://elementsgogreen.com/userfiles/file/91418943941.pdf
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160acd330894a6---tutaka.pdf
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/qskor27eg1b5pa5pu764tbcrki/kadufakeladusamawirason.pdf
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16113ddc18e44c---lezurufadem.pdf
    • https://www.espymetcalf.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081d26674302---nazarududipolaf.pdf
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/8605vir78lc1sgqaebs8gcjmth/samotobedumivale.pdf
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/f4d720769b53dd6bdd84da813a1ef9d5/31036513773.pdf
    • http://www.chicagoalphas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160983931b3c44---51169532413.pdf
    • https://justforjetscatering.com/userfiles/image/files/91586819582.pdf
    • http://slsnn.ru/content/file/dujarupidesoj.pdf
    • http://cdmvt.cz/sites/default/files/66855506657.pdf
    • https://www.koreayokogawa.com/ckfinder/userfiles/files/626657837.pdf
    • http://rusiuojigalvoji.lt/wp-content/plugins/formcraft/file-upload/server/content/files/160c6a60654b33---vijikuronu.pdf
    • http://aeklaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/noborufexogawate.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=abnormal+tamil+meaning
    • 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_off0000c850.bin
95958a9eeb9c52f072c68dea6527af8f06c14db8ae0834279a2b9b9c6a0709a1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC850 10404 bytes
font_01_sfnt_off0000dfd9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDFD9 16792 bytes
font_02_sfnt_off0000f7eb.bin
8474d5d6e1ca3b345225e35b5f284ec34629b91c3070b904d4472ce560d451cb
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7EB 21280 bytes