Malicious PDF — malware analysis report

Static analysis result for SHA-256 878a0b391b487237…

MALICIOUS

PDF

91.3 KB Created: 2021-06-28 10:33:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: ff10b772cf2b53deb1189e77aa203473 SHA-1: e3b8898078e824a26a902d94bdf7d611189390c8 SHA-256: 878a0b391b48723739cd5e051d7a766a116bef135081814408fdb44b4197875b
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple compromised WordPress sites, likely intended to host and distribute malicious files. The heuristic 'ML_NYX_PDF_MALICIOUS' strongly indicates malicious intent, and the presence of numerous external URIs suggests a phishing or malware distribution scheme. No scripts were extracted, but the structure and URLs point to a social engineering attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://cructi.ru/uplcv?utm_term=photo+viewer+free+download PDF link annotation
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1609b98dd5f42b---14668352242.pdfIn PDF document text
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f3dc83b9ad---80757625176.pdfIn PDF document text
    • http://elmiraclassiccountry.com/wp-content/plugins/super-forms/uploads/php/files/871138bopc6m07koobemlbu823/8167632517.pdfIn PDF document text
    • https://forex-robo.org/wp-content/plugins/super-forms/uploads/php/files/97fce59a574ed69658494c3dc2349ed6/49177051958.pdfIn PDF document text
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609453168291d---97795750495.pdfIn PDF document text
    • https://blsautomation.com/ckfinder/userfiles/files/53254851830.pdfIn PDF document text
    • http://hongdacable.com/d/files/42364283459.pdfIn PDF document text
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/1607bce50b5e73---nuxowojinivu.pdfIn PDF document text
    • https://corpusbg.com/files/fck/file/13144310663.pdfIn PDF document text
    • http://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afc19588421---70746529152.pdfIn PDF document text
    • http://traditionsradio.com/wp-content/plugins/super-forms/uploads/php/files/bc2roc7snbk6dh7vcuueopj5e4/newowilakedoluzejobe.pdfIn PDF document text
    • http://vote4dannybarry.com/clients/2/2f/2f5d4f67c16906f9b09010289963de11/File/44521532027.pdfIn PDF document text
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/k0ju8c4qon5vm5sg85nscrrjhb/firegu.pdfIn PDF document text
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a76e96c982---xagiduser.pdfIn PDF document text
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a240941176a---jadesovanogi.pdfIn PDF document text
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/7a35cef61def272bb84be0aa3d15efff/45315028829.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/8d8b4180974c704a0eda36749f06979f/tezefupu.pdfIn PDF document text
    • http://www.kmclogistics.com/wp-content/plugins/super-forms/uploads/php/files/e48bcb39891a4dc61093d44da93b26ae/baworu.pdfIn PDF document text
    • https://bonpetsupply.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fde48915ed---59488236384.pdfIn PDF document text
    • https://shared401k.com/wp-content/plugins/super-forms/uploads/php/files/c12c52c9d2ec9d130222f542ab9d3b2d/94733902977.pdfIn PDF document text
    • http://webcertain.net/contentupload/fckeditorUploads/organization_/file/17778155690.pdfIn PDF document text
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f6054c57e5---88194012862.pdfIn PDF document text
    • https://vyrukrc.lt/userfiles/file/75039928383.pdfIn PDF document text
    • http://thingsantiquesla.com/userfiles/files/98946591230.pdfIn PDF document text
    • 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_off0000f3f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3F7 10436 bytes
SHA-256: b3d662a6e4a9d6c07280fbb6359e5e9b361ec002a13198bbdac77728bf962cd7
font_01_sfnt_off00010b9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B9B 29148 bytes
SHA-256: 6bbf4fbb06625065eb44f1bb09c641556f5fc75283d7beb4b00a592984e66180
font_02_sfnt_off0001465c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1465C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1