Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b6cea70d89a4313…

MALICIOUS

PDF

79.8 KB Created: 2021-09-04 16:51:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: c7991f49ccf25666e5c8d6be47c08ae0 SHA-1: 7c7940bf56636340d52013229e2be6e8baa55b18 SHA-256: 7b6cea70d89a431366f35491421126a3e263fc68a00f72e1377fcb2c6c8d0131
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ML and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, pointing to numerous PDFs hosted on various domains, some of which appear to be compromised WordPress sites. The embedded URLs suggest an attempt to lure users to external content, potentially for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 https://gadd-asso.org/userfiles/file/kulukekekopajidutubagujo.pdf In PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160c92f95b7128---jukasope.pdfIn PDF document text
    • https://assurancemauricie.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f103af28252---xulivugubafiwewegirewuta.pdfIn PDF document text
    • https://onderdurdu.com/upload/ckfinder/files/11338106968.pdfIn PDF document text
    • http://murielbellhomes.com/userfiles/files/kuwinudodanuwuvag.pdfIn PDF document text
    • http://www.vljainandco.com/userfiles/files/sipolidokotenijowusod.pdfIn PDF document text
    • http://creaorganization.com/depo/sayfaresim/file/7146031543.pdfIn PDF document text
    • http://lapenya.cat/imgjovesnaves/file/mulevo.pdfIn PDF document text
    • http://saothienemb.com/uploads/images/files/61772329330.pdfIn PDF document text
    • http://amandamaitland.com/images/file/wexazekidot.pdfIn PDF document text
    • https://menu2uplus.com/images/file/ketesewutilezofunenoto.pdfIn PDF document text
    • https://veaodaibrahma.com/uploads/image/files/totodoso.pdfIn PDF document text
    • http://obasekiestates.com/UserFiles/file/81108657376.pdfIn PDF document text
    • https://siroyensao.com/upload/files/vegar.pdfIn PDF document text
    • https://www.autopsrus.com/ckfinder/userfiles/files/kijoropuxumuxolarovuleda.pdfIn PDF document text
    • https://nepalihemp.com/ckfinder/userfiles/files/96673816446.pdfIn PDF document text
    • http://pantryscan.com/123cars/imagefck/file/61210479919.pdfIn PDF document text
    • https://briljant-maleri.se/UserFiles/files/55650408412.pdfIn PDF document text
    • http://dreiseengrundschule.de/files/noguniwemida.pdfIn PDF document text
    • http://businessplan-capalpha.fr/mbp/upload/images/images/upload/ckfinder/marulinugoz.pdfIn PDF document text
    • http://fra2ange.it/userfiles/files/53130748718.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160a4a1436a8c9---gilirekanipotamolanitod.pdfIn PDF document text
    • http://fdscience.com/UPFILE/userfiles/files/46656639574.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=pathogenesis+of+essential+hypertension+pdfPDF 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_off0000d5e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5E8 16316 bytes
SHA-256: 3a36c6050832757baeecb71fd95aaf5e9ea937aa5cb124bddf1e9d870da3d217
font_01_sfnt_off00010025.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10025 10892 bytes
SHA-256: 6f0efe3ec2d7ff16f877bb1a8df5894f11ed6d536771d0a92ab185c1ffde1350
font_02_sfnt_off00011925.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11925 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1