Malicious PDF — malware analysis report

Static analysis result for SHA-256 43624c34f54f441f…

MALICIOUS

PDF

94.5 KB Created: 2021-06-28 15:15:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ded7fa0cc88133598ef3fcfa62c03ab4 SHA-1: 248b1809c25d7dce644f715e30642a98717d11dc SHA-256: 43624c34f54f441fa6f073bdc6f939729f7c386ede676a64e0afc8019f869c49
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of embedded URLs, many of which point to compromised CMS upload directories or disposable hosting. The ML classifier strongly indicated maliciousness, and the link farm structure suggests an attempt to manipulate search engine results or redirect users to malicious sites. No scripts were extracted, but the overall structure and URL patterns are indicative of a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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 http://micronforgacsolo.hu/UserFiles/file/4971623637.pdf
    • http://biirbeh.mn/images/content/file/bemavar.pdf
    • https://fulzugaskozpont.hu/files/63517855401.pdf
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/277ccdfc6974b76912a0e420021fadae/36789853282.pdf
    • https://fastcomputer.vn/wp-content/plugins/super-forms/uploads/php/files/26c0ed8c9550fd85b367982b65b5e577/budidejufotakofiwinag.pdf
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fa612dae1c---wikisozejulu.pdf
    • https://topinsolventa.ro/userfiles/file/lopenesofax.pdf
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2fd2a1768f---tuwukiwevuxanirudapedaf.pdf
    • https://chungcungoaigiao.net/uploads/files/6088556570.pdf
    • https://www.businesswatchguardingservices.co.uk/wp-content/plugins/super-forms/uploads/php/files/m1onf4966058n80fghgtrk2tes/gorowotitego.pdf
    • https://nnkcreations.com/userfiles/file/69104921399.pdf
    • https://bilbox.es/wp-content/plugins/super-forms/uploads/php/files/f0f1a2afb96378cc1e0f8a726b26febd/84923782959.pdf
    • https://clubslotalmatriche.com/calcas/file/pojofawexawatetorud.pdf
    • https://bluebeakbranding.com/wp-content/plugins/super-forms/uploads/php/files/eabad328a7f097698f40b0f699c12e61/92149539014.pdf
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/41a43e7c2bc57c76056a427741931491/vinumizofibison.pdf
    • http://xn--e1aazeoc7d.xn--p1ai/images/shared/file/95596643841.pdf
    • http://monkey-do.net/userfiles/file/74194058799.pdf
    • http://benthanhsgfarm.net/images/uploads/files/wononutilulaludosa.pdf
    • https://www.swx.global/wp-content/plugins/super-forms/uploads/php/files/b04ad1157df221adfb34a10358d186d7/67527870694.pdf
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/160806e76131ff---69856595449.pdf
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/n9nmbk4r8dbrpd3gc7tike5j65/gubinuxab.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=how+do+you+say+chicken+in+sign+language
    • 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_off00010b01.bin
00291e8cd4d997eb2f4a9b0f8bbf5e361e385ea32c036725fe8e21ccc626bbd6
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B01 10836 bytes
font_01_sfnt_off000123c1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x123C1 16792 bytes
font_02_sfnt_off00013bd3.bin
8ab46796728831a12f2854a8a996b897b03f64de7452e6037215eefbf4d3a351
pdf-font-stream PDF embedded font (sfnt) at offset 0x13BD3 19036 bytes