Malicious PDF — malware analysis report

Static analysis result for SHA-256 25db1c9c0105ba1e…

MALICIOUS

PDF

89.5 KB Created: 2021-08-07 05:41:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: ae9bbdba09cfaa14286d3cba40fd7063 SHA-1: 88b5d181c9ae4573fb190ea755941930f463deb4 SHA-256: 25db1c9c0105ba1e0496b24d8a833751ec71a6e2600185a3b5bcadf81c5a8741
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites. The ML classifier strongly indicated maliciousness, and the presence of link farms on potentially compromised infrastructure suggests an attempt to distribute malicious content or phishing lures. No scripts were extracted, but the structure and URL patterns are indicative of a malicious document designed for initial access.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16080d693bdf90---78780644461.pdf In PDF document text
    • https://cpsguffanti.com/uploads/file/87019439322.pdfIn PDF document text
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e30e6bed95---5601389091.pdfIn PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/vgfhv9ep2hbfshfnrp7lgoh5vl/vebibasubekodibizobe.pdfIn PDF document text
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/3c2860f6e88922bc1133a8d00a42fce7/80947059242.pdfIn PDF document text
    • https://noukos.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160f5326dafcf3---40074567840.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16080e2cad369f---katixafexudonijado.pdfIn PDF document text
    • http://ovartec.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e3379a9442---92538968437.pdfIn PDF document text
    • https://bdaudit.ro/userfiles/file/gigomapulofodepuwejoxi.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160edb03b11d6a---xapemiside.pdfIn PDF document text
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/6a3e9d009b8a06510376fcab5cbb6080/zizizuxalomebivusu.pdfIn PDF document text
    • https://szallas-karpatalja.com/upload/rawowutiwezerimitavona.pdfIn PDF document text
    • https://medok18.ru/wp-content/plugins/super-forms/uploads/php/files/2386871ff68c941fed9eb39b34f513c1/59432799006.pdfIn PDF document text
    • https://altonika.pro/files/fck/file/fugasurolakazunafe.pdfIn PDF document text
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/160adb9f837bdf---belabo.pdfIn PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16093b2284dbf7---69522789402.pdfIn PDF document text
    • http://elcampoeco.org/FCKeditor/file/soniwinotetobobelo.pdfIn PDF document text
    • http://drjoecarver.com/clients/49355/File/9119966977.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=f1+2020+qualifying+rulesPDF link annotation
    • 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_off0000fa64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA64 17904 bytes
SHA-256: fa29e358a5f0e5078f9772d268b27e4fec1594b06343a48234eb72b3f891442c
font_01_sfnt_off0001283f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1283F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014056.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14056 10804 bytes
SHA-256: e76faed6495a3ee51228aeaccc40c88c3343cbd1f9aa02d478857d63d73865f4