Malicious PDF — malware analysis report

Static analysis result for SHA-256 31bb6190d3b2c0b3…

MALICIOUS

PDF

113.0 KB Created: 2021-09-03 04:12:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: b74b5671f5ac9aaae60491978ab6f125 SHA-1: 6930161862ba8d32f1eb5606d715937d6c8caa58 SHA-256: 31bb6190d3b2c0b33605a1ceae1dedf220b93f143ac5283f9712cf450e8a410b
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to compromised CMS upload directories and disposable domains, indicating a link farm designed to lure users to malicious content. The ClamAV detection and ML classifier strongly suggest a phishing or trojan payload delivery. No scripts were extracted, but the structure and URL distribution are indicative of a phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

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://pistant.ru/uplcv?utm_term=sym+gts+300i+evo+service+manual PDF link annotation
    • http://fusheng-vietnam.vn/admin/webroot/upload/image/files/zigegekewor.pdfIn PDF document text
    • https://elminhaj.org/userfiles/file/zerolelan.pdfIn PDF document text
    • https://dusunceokulu.net/resimler/files/64335863944.pdfIn PDF document text
    • https://terravistahometeam.com/wp-content/plugins/super-forms/uploads/php/files/6230cbf5cb6f2321b11bcf014a99429e/mupedurifatokaveluso.pdfIn PDF document text
    • https://icnj.net/ckeditor/ckfinder/userfiles/files/38603148809.pdfIn PDF document text
    • https://ikima.fr/uploads/file/lajeruraxolamexeketow.pdfIn PDF document text
    • https://www.grandiosa.is/wp-content/plugins/super-forms/uploads/php/files/ale6eph0f495ffp0hjl2rtt2a4/13740978265.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/tjuuhref7hthp63jloip9paatk/wusefadev.pdfIn PDF document text
    • http://www.hz-kontejnery.cz/ckfinder/userfiles/files/kugojedalugobogajigagef.pdfIn PDF document text
    • http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/1rkuupu13u6jf39t55rqq185o7/91194716163.pdfIn PDF document text
    • https://cet.sk/res/file/kubuxinexekamom.pdfIn PDF document text
    • https://mk-sito.it/uploads/file/dalibemikuri.pdfIn PDF document text
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9a1d4ca18---18723166398.pdfIn PDF document text
    • https://dpengineers.info/admin/userfiles/file/vugotogozukipafedego.pdfIn PDF document text
    • http://www.petersmetalstitching.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606eedfde0a2b---ramirekabidarajegagudix.pdfIn PDF document text
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/160db7f5d026c8---nujidifumipujosetel.pdfIn PDF document text
    • https://christianklein.eu/Quansis/ckfinder/userfiles/files/gudigi.pdfIn PDF document text
    • https://rajakeempat.com/contents/files/tatigemanutovefupegenazes.pdfIn PDF document text
    • http://www.elitagida.com.tr/wp-content/plugins/super-forms/uploads/php/files/e60b63qlopu01794cn461c9000/24851291210.pdfIn PDF document text
    • https://bnbcostaverde.it/userfiles/file/82651120753.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160849d467e9e7---80706214657.pdfIn PDF document text
    • https://heatingboiler.ca/fck_upload/file/vakumapatizewapabemamis.pdfIn PDF document text
    • http://shahnawazonline.com/uploads/files/dizojeromi.pdfIn PDF document text
    • https://anmoul.com/userfiles/file/sixolusi.pdfIn PDF document text
    • http://alnadaoil.com/userfiles/file/medololisosodulozet.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_off0001518f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1518F 19352 bytes
SHA-256: e2505670f570b1e452f7f35b26e43de61418bc1fc99ae4ac64c5d98553868d44
font_01_sfnt_off00018400.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18400 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00019c17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19C17 11224 bytes
SHA-256: 52f74bb6a7403efb3b811fc57412c6932390640598d56eac69c0f31dba384b9f