Malicious PDF — malware analysis report

Static analysis result for SHA-256 5ffdec756718d7e7…

MALICIOUS

PDF

79.9 KB Created: 2021-09-18 00:11:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 141996e5ad0fb8cc7bc8e07fba9d7a96 SHA-1: 81d06f824ec742ab62e3ee022cc0e0af768c879c SHA-256: 5ffdec756718d7e7ee64a8ac1355e91c54593e8e95f8a71d4d699277d6f7a597
96 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

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 https://philabc.ru/uplcv?utm_term=edit+apk+file PDF link annotation
    • http://citescolairedeledit.com/include/file/refinodatibavutewopotenos.pdfIn PDF document text
    • https://aurorabersinar2.com/contents/files/66008620311.pdfIn PDF document text
    • http://networkinglikepro.com/ckfinder/userfiles/files/69609081365.pdfIn PDF document text
    • http://www.smartusb.info/images/library/File/sajixovusog.pdfIn PDF document text
    • http://rnralpha.cz/res/file/toxusuxikutix.pdfIn PDF document text
    • http://quincy.pl/ckfinder/userfiles/files/79696380534.pdfIn PDF document text
    • https://charming-dc.com/uploads/files/202109061805377371.pdfIn PDF document text
    • http://maremio.ru/admin/ckfinder/userfiles/files/92613057002.pdfIn PDF document text
    • http://ankaraeksioglu.com/resimler/files/rogomemerikememebuj.pdfIn PDF document text
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138f7be97476---48696891557.pdfIn PDF document text
    • https://www.babetravelling.com/ckfinder/userfiles2/files/37027380185.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133c1d1d40ec---mojipaluzideturi.pdfIn PDF document text
    • http://ladyqueen.it/userfiles/files/fezub.pdfIn PDF document text
    • http://gazomotor.com/allinone/file/vaxogusetonami.pdfIn PDF document text
    • https://cornerstonelaw.eu/userfiles/file/77882552004.pdfIn PDF document text
    • http://hkxhjfc.ltd/uploads/files/20210917152628.pdfIn PDF document text
    • http://bscartridge.com/pic/93943367962.pdfIn PDF document text
    • https://csn-alliance.com/data/files/nosisamukuzusurosojus.pdfIn PDF document text
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/cc4e15c45463846f4078ff79a34c1fc3/37436092352.pdfIn PDF document text
    • http://fatimaartwork.com/userfiles/file/62718725668.pdfIn PDF document text
    • https://sevenhillsgroup.net/ckfinder/userfiles/files/vuruledijamazodexevovene.pdfIn PDF document text
    • https://darshanam.com/ckfinder/userfiles/files/50111486921.pdfIn PDF document text
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/i1eqfthua5hi6r8er4ldqsdgpo/wupovaxowisaji.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141ccd68c1c6---80297588665.pdfIn PDF document text
    • http://fireprovietnam.net/luutru/files/33582167981.pdfIn PDF document text
    • http://www.alliance-bio.com/user_data/editor/ckfinder/core/connector/php/upload/files/mamidu.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_off0000d5c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5C0 17904 bytes
SHA-256: e79b0a33b629780138cdc865f58a1ff9cda313c891224a01da86d0e230887414
font_01_sfnt_off000103ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103EE 10076 bytes
SHA-256: 6605e4b1b396df5940cf428ceaaa68d2578ec5ec670468e014244eac51942445
font_02_sfnt_off00011a78.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A78 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1