Malicious PDF — malware analysis report

Static analysis result for SHA-256 340738b94a5c4cef…

MALICIOUS

PDF

84.1 KB Created: 2021-06-29 15:01:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 6158c421589005e7d5f40fa98b79cd2d SHA-1: 4d6f2cbaa045c6d609c43e4c846fa16b6a5e56d2 SHA-256: 340738b94a5c4cef7cd2047316711609c3eb09a537c1eaafb2189e758c2171ce
96 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs pointing to compromised WordPress sites, indicating it functions as a link farm. The ML classifier strongly flagged this PDF as malicious, and the presence of multiple distinct hosts hosting PDF files suggests a coordinated effort to redirect users to potentially harmful content. No scripts were extracted, but the primary attack pattern is the distribution of malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://crewmak.ru/uplcv?utm_term=what+countries+have+a+unitary+system+of+government PDF link annotation
    • http://svenstavik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160861119417a9---90188442799.pdfIn PDF document text
    • https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b3dfb29117a---96602237418.pdfIn PDF document text
    • https://serwisnawigacji.pl/userfiles/file/11412614483.pdfIn PDF document text
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/l31polgdmb3qd8ehkl01mo0ooo/35286437131.pdfIn PDF document text
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/288db9b346523ee5e75d173a1fb5e039/66572053566.pdfIn PDF document text
    • https://singaporenotarypublic.com/wp-content/plugins/super-forms/uploads/php/files/fdd4e10ad0bbeb9ef273598004ba90c7/70855471399.pdfIn PDF document text
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078c69028541---52253401727.pdfIn PDF document text
    • http://www.gaviprintpack.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607da0ff17d42---1652733931.pdfIn PDF document text
    • https://aadhaarretail.com/administrator/imagetemp/file/fafemunebobaner.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/160a0b17c0199f---81235514201.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd659366901---nepozefuwir.pdfIn PDF document text
    • http://uk-finansist.ru/userfiles/file/78700955106.pdfIn PDF document text
    • http://amuseonline.com/absite/userfiles/file/jetoxusaxibupevemus.pdfIn PDF document text
    • https://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/6abf353d420012ddb053a795b94550d0/vogesiver.pdfIn PDF document text
    • http://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf00523d5c7---27976680875.pdfIn PDF document text
    • https://hansenlight.com/UploadFile/files/fisikukujulu.pdfIn PDF document text
    • https://cor.org.ar/wp-content/plugins/super-forms/uploads/php/files/qlbq50idl8kcg2c1eket2v1rlk/50305342631.pdfIn PDF document text
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/e3b35e0ed47b4d0189585d89d537ac87/siwuza.pdfIn PDF document text
    • https://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/160922924e9bc3---dinizoxetarolewup.pdfIn PDF document text
    • http://bitite.lv/media/txt/122/file/19546090507.pdfIn PDF document text
    • https://grand-forge.ru/wp-content/plugins/super-forms/uploads/php/files/a4401edcedbd82884e3139dcfd8b3e32/79386699023.pdfIn PDF document text
    • http://www.derbysignandgraphics.com/uploads/file/81685775627.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_off0000e49e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE49E 11008 bytes
SHA-256: ec0901d67dce99040cd820ca13d1c423df054b0b3000fa67c0c7e7a5704316a8
font_01_sfnt_off0000fe23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE23 17112 bytes
SHA-256: 803b038b318468c8ec3ce53dc79ee396d78c986a53826dadcbe109f256350edc
font_02_sfnt_off00012aaa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AAA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1