Malicious PDF — malware analysis report

Static analysis result for SHA-256 e2cebf50f16ad9c7…

MALICIOUS

PDF

78.3 KB Created: 2021-09-03 08:22:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: c1fada77935a7d62e3fdb5b7f0f76660 SHA-1: 09ffa9f67643b74ae942459b4a3a8388b6344692 SHA-256: e2cebf50f16ad9c7b3b93d24847ee005a2ac1f1f0a64a986102d50c935f6b9b4
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 0.9978

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://inwebjor.ru/uplcv?utm_term=cell+membrane+and+transport+review+worksheet+answers PDF link annotation
    • https://trvstore.com/userfiles/file/7925046676.pdfIn PDF document text
    • http://multi-accueil.fr/ressource/site-image/files/vunafijitofa.pdfIn PDF document text
    • https://landlorddebtadvisory.com/wp-content/plugins/super-forms/uploads/php/files/4shbbmdmttpv1ct3j81ghriuo0/77632388276.pdfIn PDF document text
    • https://event-connections.net/wp-content/plugins/formcraft/file-upload/server/content/files/1606f14a896077---87275841426.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16076b40dcd104---16151734103.pdfIn PDF document text
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/61a6ce353ea1f80b421ba248ae84d876/metefigulugabixali.pdfIn PDF document text
    • http://elskup.pl/images/assets/file/fetigomas.pdfIn PDF document text
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/a9428b440a199d147cee705f4680aa4f/woguvifewijurededu.pdfIn PDF document text
    • http://nanoservice.cz/upload/file/witas.pdfIn PDF document text
    • https://rolcsi-bau.hu/userfiles/files/besosenikewovedakoxemokiv.pdfIn PDF document text
    • http://abwingsva.com/uploads/files/jifolakuzajuwariwumi.pdfIn PDF document text
    • http://quocteanviet.com/img-chamthi/files/wigejibimixalevulekewa.pdfIn PDF document text
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608933a400101---dekurokuta.pdfIn PDF document text
    • http://sysquare.com/UserFiles/files/bafapog.pdfIn PDF document text
    • http://xn--80aafbkbafwdti1ahihccrg.xn--p1ai/pict/file/5465349396.pdfIn PDF document text
    • http://abacusnancy.com/userfiles/file/tazozivikenele.pdfIn PDF document text
    • http://praxis-greve-polley.de/web/editor/files/biwuramuxonemujot.pdfIn PDF document text
    • https://rzfmuhasebe.com/userfiles/file/35195077788.pdfIn PDF document text
    • http://www.caribbeandentist.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5598197a86---32087736749.pdfIn PDF document text
    • http://shriadinathbank.com/uploads/34301040434.pdfIn PDF document text
    • http://goldmustang.ru/files/files/bowijebo.pdfIn PDF document text
    • https://invest.pl/userfiles/file/40167538806.pdfIn PDF document text
    • http://minhvuongthuphap.com/upload/ck/files/liwajum.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_off0000cecb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCECB 11072 bytes
SHA-256: dab28fa010365ec071bd187e2e073a14e4314c6a8535e825a409aa373afcd006
font_01_sfnt_off0000e831.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE831 16752 bytes
SHA-256: 79c1fd7c7e7a991fc9471ef29c2ea30a1549829d298afdd9e3d766fa870d536e
font_02_sfnt_off00011331.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11331 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1