Malicious PDF — malware analysis report

Static analysis result for SHA-256 64f9a322ea347728…

MALICIOUS

PDF

72.5 KB Created: 2021-09-07 06:57:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 42ccf22bf6608e28c0beba5223a734b3 SHA-1: cbc5f13c3073baddee3cd8ca9f79d556e40e09ec SHA-256: 64f9a322ea34772894a513e257382c0bbc6717922727a5f01a62fc845b819fbd
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories. These links appear to form a link farm, likely intended to manipulate search engine rankings or distribute further malicious content. The ML classifier strongly indicated maliciousness, supporting the assessment of a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/1610a3ca7b265a---kajodijerasi.pdf In PDF document text
    • https://2ruoteexpo.it/ckfinder/userfiles/files/darifopi.pdfIn PDF document text
    • https://dipinkrishna.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abf22085b6d---61787125862.pdfIn PDF document text
    • http://hoondb.com/wp-content/plugins/formcraft/file-upload/server/content/files/160805dcba4746---futurebup.pdfIn PDF document text
    • http://yishiweb.com/upfiles/files/20210602_201620.pdfIn PDF document text
    • http://winhazel.com/indigo/ckfinder/userfiles/files/7205734650.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b65bf87ec84---2458209664.pdfIn PDF document text
    • https://advancedcheckcashadvance.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079550ba0422---joxepufopusifuz.pdfIn PDF document text
    • http://asclyziarskyklub.sk/userfiles/file/mopadupor.pdfIn PDF document text
    • https://embassyinvietnam.com/webroot/img/files/vigeratipibuxomeset.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/2d3c03e88068196a797ac20da333806d/81885076188.pdfIn PDF document text
    • http://www.gunyagder.org.tr/wp-content/plugins/super-forms/uploads/php/files/c2jo1q8nalv8hv6cdoq8duo0l4/nonuzaxaredebilagogujur.pdfIn PDF document text
    • http://vytvarnyobchod.cz/UserFiles/File/93543400664.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/34000021309.pdfIn PDF document text
    • http://mdknoodles.co/uploads/files/42024823670.pdfIn PDF document text
    • http://homestationrealty.com/userfiles/files/taguwoxaxesodepodepu.pdfIn PDF document text
    • https://kuepancong.com/contents//files/22638855809.pdfIn PDF document text
    • https://ms02bet.com/contents/files/nowiguzonubasitotujabe.pdfIn PDF document text
    • http://akicgiyim.com/userfiles/file/60474560858.pdfIn PDF document text
    • http://hugslock.com/app/webroot/img/files/24522696198.pdfIn PDF document text
    • https://prestinieurope.ch/userfiles/files/mivejotivumevusaduwe.pdfIn PDF document text
    • https://eternalbliss.net/file/nunazuzowaxutoxozosafogo.pdfIn PDF document text
    • http://bycongroup.com/UserFiles/file/bimasojuxorof.pdfIn PDF document text
    • https://hagakure.by/upload/editor/files/mebiwubaxifowujuson.pdfIn PDF document text
    • https://inchiriereelicopterromania.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160db95edcec8f---80499869790.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=introduction+to+radar+systems+merrill+skolnik+pdfPDF 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_off0000bc89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC89 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d49b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD49B 14832 bytes
SHA-256: ca297d0d62e6a54f73260e9fd45641182a64aef1679b5f07b35dc8570cb685cc
font_02_sfnt_off0000fa4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA4D 11040 bytes
SHA-256: 0ac352badd6cb39e7dab49c3912ce3df42ed9e453efcf839a4770db97c2c5b98