Malicious PDF — malware analysis report

Static analysis result for SHA-256 88c74058fef60fd4…

MALICIOUS

PDF

69.4 KB Created: 2021-09-06 16:51:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 392c654d3c096992c78495bb419ff176 SHA-1: 366b36d821a89f08fb706c600bf11e7594bd3634 SHA-256: 88c74058fef60fd4d11e89f956262a53dce4597e0810710b65eaab500a8cf88f
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 0.9956

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://cructi.ru/uplcv?utm_term=singer+sewing+machine+user+manual+pdf PDF link annotation
    • https://hizlipin.com/calisma2/files/uploads/totemazewudapun.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160818c90ca0fe---56427463121.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/41932308570.pdfIn PDF document text
    • http://carsonpokebar.com/uploads/files/dujagufipiwenuwujilegaz.pdfIn PDF document text
    • http://altadirezione-consulting.it/userfiles/files/nuvexoguku.pdfIn PDF document text
    • https://alatheir.com/atheirwsfiles/file/53507464969.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160d63b3dad4ec---88338233562.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a8e75459908---90990072333.pdfIn PDF document text
    • https://www.sanier.pl/wp-content/plugins/super-forms/uploads/php/files/tjpgcoechnsam1717ohkr5ilfe/burusemapijas.pdfIn PDF document text
    • http://www.tobywells.org/media/fckdir/file/tanadebuf.pdfIn PDF document text
    • http://euro-ex.net/images/blog//file/voxem.pdfIn PDF document text
    • http://anhuizpyy.com/upload_fck/file/2021-5-18/20210518084804687553.pdfIn PDF document text
    • http://derma-dts.de/files/file/9100695104.pdfIn PDF document text
    • http://alpanelektrik.com/depo/sayfaresim/file/5171219727.pdfIn PDF document text
    • http://podwierzba.eu/ckfinder/userfiles/files/19792258713.pdfIn PDF document text
    • http://art-ball.net/files/file/logonozijut.pdfIn PDF document text
    • http://www.smakbyala.com/ckfinder/userfiles/files/mijegonutuzerobod.pdfIn PDF document text
    • https://realestateconnect.biz/wp-content/plugins/super-forms/uploads/php/files/jf8s9i2vu00oep5ic3sepalen3/32485260821.pdfIn PDF document text
    • https://www.andrecampbell.ca/wp-content/plugins/super-forms/uploads/php/files/c4455366ccfad92ecc34ca43ae90b2b0/rusuju.pdfIn PDF document text
    • http://maynenkhipuma.vn/quangbasanpham/app/webroot/upload/image/files/sigavibosozikaretowasi.pdfIn PDF document text
    • http://abwalabamaave.com/uploads/files/39069110575.pdfIn PDF document text
    • https://vuaship.com/wp-content/plugins/super-forms/uploads/php/files/8eqkbhcu0mjahco3fg9g6hufu5/14509510625.pdfIn PDF document text
    • https://readxyz.com/wp-content/plugins/super-forms/uploads/php/files/4836a1559589a8f20eb2f409ffa7f223/bozenarusetegidet.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_off0000b2ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2CA 14308 bytes
SHA-256: 5b9da91c522c21f5cc1faf47c38b6e3c1475162a67f54225d4ca3f86ee4e50f7
font_01_sfnt_off0000d65f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD65F 11108 bytes
SHA-256: c534aae880fa34e2a82ecf13c177bc52b8a142a3445be02b78ff424fd2d23fee
font_02_sfnt_off0000efe4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFE4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1