Malicious PDF — malware analysis report

Static analysis result for SHA-256 6fd37162712fa72b…

MALICIOUS

PDF

81.2 KB Created: 2021-09-09 11:33:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-27
MD5: ac2d53210f8e5cfbdc3d7ca526154fb2 SHA-1: 0314e94e3da50aa8b6500b91ebb267e4bb0e80f3 SHA-256: 6fd37162712fa72bba9c71e37ae5dbeb9888c69c67641437d71f456ca02933c1
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable domains or compromised CMS upload directories, indicating a link farm or distribution mechanism. The ML classifier strongly flagged this PDF as malicious. While no scripts were extracted, the presence of multiple external links suggests an attempt to redirect users to malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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 http://tobn56.com/UpFiles/file/79543544286.pdf In PDF document text
    • http://ustunongel.com/image/files/nababos.pdfIn PDF document text
    • https://centrorevisionimonregalese.it/file/jemav.pdfIn PDF document text
    • https://pass-eco-energies.com/ckfinder/userfiles/files/tuxupojukuzebizurilawilef.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/161308fcfd808e---mumorenapa.pdfIn PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/161395c2b51957---mezasunekewamim.pdfIn PDF document text
    • https://heuresromantiques.com/upload/files/wikamo.pdfIn PDF document text
    • http://compsult.net/userfiles/file/tevonoponugasedu.pdfIn PDF document text
    • http://avtosfera28.ru/userfiles/file/xixew.pdfIn PDF document text
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/84823770d342ae1865babd40c0780cc8/12180453274.pdfIn PDF document text
    • http://kystar.net/filespath/files/20210908054520.pdfIn PDF document text
    • http://first-group.kr/ckupload/files/sozujosowetogez.pdfIn PDF document text
    • http://videofilm-tv.ru/content/File/xamigoferunaxibop.pdfIn PDF document text
    • https://plasy.com/uploads/file/wasutavimuju.pdfIn PDF document text
    • http://cuanhuaabshanquoc.vn/files/kunimaxetatazelenazi.pdfIn PDF document text
    • https://baruipur.org/ckfinder/userfiles/files/lovuvanibeniko.pdfIn PDF document text
    • http://itkaufmann.com/images/fckimages/file/29838081687.pdfIn PDF document text
    • http://yoga-privates.com/yoga-privates/file/vanusamuxeka.pdfIn PDF document text
    • http://www.psychophonie-tarbes.com/ckfinder/userfiles/files/nibuvifo.pdfIn PDF document text
    • http://gugugroup.com/userfiles/135917264.pdfIn PDF document text
    • http://gpmpoolandspa.com/ckfinder/userfiles/files/nibobanezo.pdfIn PDF document text
    • http://esipro.fr/userfiles/file/perazejojoz.pdfIn PDF document text
    • http://studiostocchi.eu/userfiles/files/92837541290.pdfIn PDF document text
    • http://inphuduong.vn/upload/files/jononudekojiwabakumodinu.pdfIn PDF document text
    • http://uro-medical.pl/zdjecia/fotki/file/fatox.pdfIn PDF document text
    • http://studioarchperissinotto.eu/userfiles/files/79996541920.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=weather+live+mod+apkPDF 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_off0000d933.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD933 17640 bytes
SHA-256: 6da75dc09c1774894ee2c7f504f6cff2d15cddd934ceb935b93b576fbac6f2bf
font_01_sfnt_off00010776.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10776 10536 bytes
SHA-256: 7c9939346f69fa13ec47bcc4a83a39e213b24585b70a3dbd1ded354f1a9bf316
font_02_sfnt_off00011f71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F71 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1