Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdc1f99509df952a…

MALICIOUS

PDF

83.4 KB Created: 2021-06-30 23:44:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 7cdda91875b0c59980733fe72a85860f SHA-1: e919e2c752bc79f9a773e646a4f7816434002fb5 SHA-256: cdc1f99509df952ad17950ae1a5f81505439794aaedd56f57078b8e1244b5ba2
96 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 compromised WordPress sites. The ML classifier strongly indicated maliciousness, and heuristics identified it as a link farm on disposable hosting. While no scripts were extracted, the structure and URL patterns suggest an attempt to lure users to external sites, likely for further exploitation or phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 5

  • 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://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608c9f3786e8a---48567873137.pdf In PDF document text
    • https://yziact.fr/wp-content/plugins/super-forms/uploads/php/files/8kj7e29vdvnub9r4l4na0g10qk/56387556651.pdfIn PDF document text
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160720fa35165a---ruxadadafuwiravolasedigub.pdfIn PDF document text
    • https://karapinarinsaat.net/userfiles/upload/file/85149984221.pdfIn PDF document text
    • https://medok18.ru/wp-content/plugins/super-forms/uploads/php/files/29888c522d80fbdb7a557888a1088402/firatuviluxus.pdfIn PDF document text
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160b7c8fe15aec---52556868188.pdfIn PDF document text
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/160bf5e999a2d3---dabapevulumedofowekimak.pdfIn PDF document text
    • http://vilaportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a63d07442ef---6117965988.pdfIn PDF document text
    • https://amrapalispot.com/userfiles/file/77338968094.pdfIn PDF document text
    • https://jooli.ru/ckfinder/userfiles/files/83583822770.pdfIn PDF document text
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d955d76d9e---61860093335.pdfIn PDF document text
    • http://tubietelbar.hu/uploadfile/72203072638.pdfIn PDF document text
    • https://samyenngochoang.com/wp-content/plugins/super-forms/uploads/php/files/85gqaml8mccfafdbaak5ops6f1/rebubuwixodu.pdfIn PDF document text
    • http://slsnn.ru/content/file/befifolememopukogoso.pdfIn PDF document text
    • http://2478.ru/admin/ckfinder/userfiles/files/31635919376.pdfIn PDF document text
    • https://www.c2commercial.com/wp-content/plugins/super-forms/uploads/php/files/0f22f8360b51b3ecaab8564eda4aff76/7190164564.pdfIn PDF document text
    • http://www.deco-interieure.com/userfiles/file/6797605111.pdfIn PDF document text
    • https://securitegenerale.tn/userfiles/file/nivazosijogidofanada.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1606d6cffda30f---76981172710.pdfIn PDF document text
    • https://ewms.vn/wp-content/plugins/super-forms/uploads/php/files/nd84ciq58hef8dgov66kmaqjra/virujaraxusuz.pdfIn PDF document text
    • http://www.heksan.com.pl/file/75125993797.pdfIn PDF document text
    • https://vinisfarm.com/wp-content/plugins/super-forms/uploads/php/files/c100ecfb5b6ed8888615e596b5d68fe1/86775565523.pdfIn PDF document text
    • https://landlorddebtadvisory.com/wp-content/plugins/super-forms/uploads/php/files/bhg0ljiijjfg0bjkiiuf7f4um5/ranexanofisula.pdfIn PDF document text
    • http://banghetretruc.com/media/ftp/file/xelujod.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=why+my+fire+tv+remote+is+not+workingPDF 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_off0000e3df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3DF 10804 bytes
SHA-256: 609113ba1f94b6a90082079bf98178711a4e46d0b37a34fb37d216e36cc99ffb
font_01_sfnt_off0000fcae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCAE 16796 bytes
SHA-256: 0555f388acc358993f1c15528b5b1cead025fed97febda534a70ca53468d3fb3
font_02_sfnt_off00012852.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12852 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1