Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf0c026629284776…

MALICIOUS

PDF

69.8 KB Created: 2021-09-14 08:42:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 986ba7e34604c7168b850ae09cff2417 SHA-1: e5d040cc313b95b703f6400a5b311c564032e8f2 SHA-256: cf0c026629284776e74b1fbc7299c34445f510751ea4b31e9f2e807e786a7fd6
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple external URIs, many of which point to compromised WordPress sites or disposable hosting. These links appear to form a link farm, likely intended to redirect users to malicious content or further stages of an attack. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://mu-rrrc.com/userfiles/file/10425703414.pdf In PDF document text
    • http://cosyromania.com/media/file/68808209466.pdfIn PDF document text
    • http://www.syrahresources.com.au/application/third_party/ckfinder/userfiles/files/83593932528.pdfIn PDF document text
    • https://tiklatakip.com/calisma2/files/uploads/98074345251.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139f85496a43---kowarogiwetufibuma.pdfIn PDF document text
    • http://donovaly-ubytovanie-safran.sk/web/userfiles/file/5271999588.pdfIn PDF document text
    • http://logisticsnetworks.net/ckfinder/userfiles/files/xunibodixani.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613d883a37783---66753612852.pdfIn PDF document text
    • https://spcinternational.in/ckfinder/userfiles/files/14221377246.pdfIn PDF document text
    • http://gz-theoutfit.com/UploadFiles/FCKeditor/20210908232301.pdfIn PDF document text
    • http://bordahusfeldolgozo.hu/editor_up/67923779510.pdfIn PDF document text
    • https://yellowstonewildlife.com/welavadulagaxagupiborete.pdfIn PDF document text
    • http://vanprodukt.cz/UserFiles/File/vejiburevoxisima.pdfIn PDF document text
    • http://levne-pohary.cz/UserFiles/File/34308395362.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/161300460c9af7---fedarew.pdfIn PDF document text
    • http://www.thegrcinstitute.org/app/webroot/js/ckfinder/userfiles/files/18642215764.pdfIn PDF document text
    • http://www.gradur.ba/wp-content/plugins/formcraft/file-upload/server/content/files/1613fdf74ac805---90033296244.pdfIn PDF document text
    • http://begemot-rus.com/uploadfiles/file/2021090218001273499.pdfIn PDF document text
    • http://flyingkirin.com/uploadfiles/file/110946011109.pdfIn PDF document text
    • http://www.anglometais.com.br/adm/Editor/ckfinder/userfiles/files/9661744702.pdfIn PDF document text
    • http://sinproval.it/userfiles/files/61070548150.pdfIn PDF document text
    • http://agisinfo.ru/uploads/content/files/9635267153.pdfIn PDF document text
    • http://theponghop.com/upload/files/54814471081.pdfIn PDF document text
    • https://jjcfurnituremaker.com/userfiles/files/bapekubovowujewobidu.pdfIn PDF document text
    • http://iamsong.vn/uploads/files/kakefemopipamig.pdfIn PDF document text
    • http://changrung.com/ckfinder/userfiles/files/robuzubodelabazej.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=virtual+tennis+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_off0000b46b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB46B 10712 bytes
SHA-256: b207ea841f601c3c6b1537c3cf95e24384795e52908ff6509bdde1d586fa51ed
font_01_sfnt_off0000ccfa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCFA 14904 bytes
SHA-256: 4072d23e5856bc1b083a1f1a932be56679ed3282ae4360245241c5ffc5fc76d2
font_02_sfnt_off0000f1f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1F7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1