Malicious PDF — malware analysis report

Static analysis result for SHA-256 19f3cd4fad0b7873…

MALICIOUS

PDF

84.1 KB Created: 2021-07-03 11:13:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6e20d4ada89e1a98493c95c6cf1b2c21 SHA-1: dd74e5815d2d235141a3c5dcade121faacb21b42 SHA-256: 19f3cd4fad0b7873981555bfe8bba4d07c843527668931c67f4635bcc6089751
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm for SEO manipulation or to distribute further malicious content. The ML classifier strongly indicated maliciousness. While no scripts were explicitly extracted, the nature of the links and the PDF structure point towards a phishing or content distribution vector, likely initiated via a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://infrive.ru/uplcv?utm_term=personal+swot+analysis+for+interview
    • https://corpusbg.com/files/fck/file/4687412809.pdf
    • http://eot.mn/uploads/userfiles/files/82626274267.pdf
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c8214dc9b4---rinikenafuzadekaxono.pdf
    • http://rocb-ap.org/file_media/file_image/file/xuxefafeb.pdf
    • http://aelma.com/sites/default/userfiles/file/41112433653.pdf
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160808198705b0---63575539144.pdf
    • https://bruceleevideos.org/images/file/70154197582.pdf
    • http://srihemkuntsahibfgp.org/hemkunt/userfiles/file/26562141871.pdf
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160c98505ee758---77818700868.pdf
    • https://gbeequestriansurfaces.com/wp-content/plugins/super-forms/uploads/php/files/v9v6qmjrgo7iqgtjkpbdkjoj9a/fekobopiva.pdf
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8861d7feff---63656089994.pdf
    • http://chrisnoblelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/bekekere.pdf
    • https://gradeagroup.com/wp-content/plugins/super-forms/uploads/php/files/76rnhjmmgm1khog21sv5690490/jezefopofoxu.pdf
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/160df6033c70c3---napifilidozefebegabudo.pdf
    • https://christembassyromford.org/wp-content/plugins/super-forms/uploads/php/files/57f2dffe626e028c690f2e9ec153a745/93386665633.pdf
    • https://floridaholidayplanner.com/wp-content/plugins/super-forms/uploads/php/files/1ea89ab5f162417f24aa90d9595ed6be/61883375397.pdf
    • https://local-atlas.ru/userfiles/files/15037432236.pdf
    • https://www.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/160c8790347802---13890641395.pdf
    • http://xn----dtbsgbucafmmaf.xn--p1ai/servimages/editor/files/jegubogoturexov.pdf
    • http://cukiernia-waltar.pl/qcms/userfiles/file/pededovifo.pdf
    • https://motelandratecuci.ro/userfiles/file/xidipojazo.pdf
    • http://xoblates.com/clients/e/e0/e08cfb93fb97b00c28394d0532709dc9/File/7073464748.pdf
    • http://scard.vn/app/webroot/uploads/files/52994574112.pdf
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160be541beb0d8---67394674906.pdf
    • https://www.glasswindowequipment.com/wp-content/plugins/super-forms/uploads/php/files/92ce02876df5fdc68de74f4586faa76e/82610875420.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e933.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE933 16792 bytes
font_01_sfnt_off00010145.bin
6ec4367e176a504514e171eb7678f3f2b93b7acf53ca5cf882421658940307cb
pdf-font-stream PDF embedded font (sfnt) at offset 0x10145 16224 bytes
font_02_sfnt_off00012b1b.bin
e1a5ba2e7a541c9555069f209f7f8160e949145187cf20ab6f335bdb1acafadb
pdf-font-stream PDF embedded font (sfnt) at offset 0x12B1B 10476 bytes