Malicious PDF — malware analysis report

Static analysis result for SHA-256 d482652336f17af0…

MALICIOUS

PDF

70.2 KB Created: 2021-09-25 06:59:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: c232f014fde89482f0f12239a2f5d3c2 SHA-1: 7a7531390332e364c93817f50a67336323348f2a SHA-256: d482652336f17af07676f2d398fe42ae1d119c59c790b5c3703586febc73bb05
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to various domains, many of which appear to be compromised or disposable hosting. The ML classifier strongly indicated maliciousness, and the PDF structure suggests it's designed as a link farm to distribute malicious content or phish users. No scripts were extracted, but the heuristic firings and URL analysis point to a malicious link distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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=android+in+app+purchase+hack PDF link annotation
    • http://steinbach.casawell.tw/userfiles/file/terulukiduwo.pdfIn PDF document text
    • https://natyabio.com/uploadfiles/13880825180.pdfIn PDF document text
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613d257e27efd---rulatururezepekopig.pdfIn PDF document text
    • http://aolisenjiancai.com/data/files/82945664620.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614d0c3ee6777---1438253026.pdfIn PDF document text
    • http://1-champagne.com/blog_images/blog_/file/15658607073.pdfIn PDF document text
    • http://tungalag.mn/userfiles/files/bisojisusiwupedotipetet.pdfIn PDF document text
    • http://dlevitin.ru/fck_editor_files/files/xijebos.pdfIn PDF document text
    • http://invismortgagebroker.com/images/file/rukef.pdfIn PDF document text
    • https://glycocalyx.nl/userfiles/image/file/44113519811.pdfIn PDF document text
    • http://sevinctekstil.com/resimler/files/42746249645.pdfIn PDF document text
    • http://laarakkers.com/ckfinder/userfiles/files/rigatigibulap.pdfIn PDF document text
    • http://appinaris.net/ckfinder/userfiles/publics/files/nopig.pdfIn PDF document text
    • http://eapver.com/upload/ckimg/files/202109170015035054.pdfIn PDF document text
    • http://gzky.cn/dubeite/ckfinder/userfiles/files/20210903_221730.pdfIn PDF document text
    • https://www.xcelsus.de/wp-content/plugins/formcraft/file-upload/server/content/files/16146c75f395a6---24926103919.pdfIn PDF document text
    • https://akconta.com/uploads/files/sogawuwop.pdfIn PDF document text
    • http://megaprestige.ru/uploads/files/geponozekewukodu.pdfIn PDF document text
    • http://www.saveurspoitoucharentes.com/admin/ckfinder/userfiles/files/76798906819.pdfIn PDF document text
    • http://blfimmobiliare.com/userfiles/files/gajomugelemejosu.pdfIn PDF document text
    • http://historia-bfured.hu/userfiles/file/doxunezupovelerejibomoke.pdfIn PDF document text
    • http://findmecakes.com/userfiles/files/49783836265.pdfIn PDF document text
    • http://manchetenewsms.com.br/ckfinder/userfiles/files/wudizefapap.pdfIn PDF document text
    • http://werkschoenenverkoop.nl/images/docman/files/88524792964.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_off0000b42d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB42D 10640 bytes
SHA-256: f2d9bd63bddad67e459b6f01ac541c6d4b084b10553f476720179cce786c460c
font_01_sfnt_off0000cc76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC76 15588 bytes
SHA-256: ed85a65ac352ea047ef011636915c23dce97ecca74b45a4c3dacf98df0c085c1
font_02_sfnt_off0000f305.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF305 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1