Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb0a6c03c0b37c10…

MALICIOUS

PDF

80.7 KB Created: 2021-07-02 12:17:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3260fa781871440b65f1ad157dfb6ce7 SHA-1: 0149861b6f4cd847418ae0a98d4d1ca545296f62 SHA-256: cb0a6c03c0b37c10064ad89ee11cbe5eb0e6d74bf5cfbd013dd32c041db4e91c
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous compromised websites, as indicated by heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM'. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution via these external links. No scripts were extracted, but the structure itself is designed to lure users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8008b87eef---sefixamirujoda.pdf
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/9b83af952f72695911fcddac20524b9a/98996620871.pdf
    • http://pcwenhua.com/uploadimg/file/1622609417653749243.pdf
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/16081869332fc4---nejerutujijesik.pdf
    • https://www.harasportcenter.com/wp-content/plugins/super-forms/uploads/php/files/1q939u6odhu96b4cufafhq7o4o/55378313049.pdf
    • https://fourseasons.events/wp-content/plugins/super-forms/uploads/php/files/918a111ae1c7bc31b4711b67c0445ec8/lawogubelinet.pdf
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/160aa78907381c---8168898799.pdf
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/160757eef3da06---94287106706.pdf
    • https://efnnma.org/files/file/mivipagiboxowa.pdf
    • http://menafundinfo.com/userfiles/file/pisikemaginex.pdf
    • http://amirafouad.com/uploaded_files/file/guxuwagofadovoketalezeto.pdf
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/16078c3d7c5413---90260054933.pdf
    • https://c4ir.ae/wp-content/plugins/super-forms/uploads/php/files/sg1db2cr30lrbaugkgl3p7fon6/rapofiseriwudij.pdf
    • https://gomaihoa.net/upload/files/17622933350.pdf
    • http://sweetbasketsbyjackie.com/clients/864293/File/6445536054.pdf
    • http://debden.org/userfiles/file/somofugubudozapef.pdf
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9a7f06ca6---94075167388.pdf
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/a79837e31dba212deb3d419b315bf787/68708602708.pdf
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/48d919f380fff3ae7ea025be5b9b5690/71171638779.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=two+row+rice+transplanter
    • 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_off0000daaf.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDAAF 16792 bytes
font_01_sfnt_off0000f2c1.bin
8d924e827fad29d50fe5bbd0c8292a3d8d853735aa48d90b9b6ca2cd2812b8a2
pdf-font-stream PDF embedded font (sfnt) at offset 0xF2C1 16620 bytes
font_02_sfnt_off00011e16.bin
d6eb3fc3cecfc85587f2e455954e2b2a93b226d8fbc5af5b252cc128aac5fa90
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E16 10416 bytes