Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a1177611d5212d3…

MALICIOUS

PDF

92.2 KB Created: 2021-07-29 21:33:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cf26f896a29b9c3b62ffb989159fa31e SHA-1: 738c676262f1225926aba2dc221d777b46764f2f SHA-256: 7a1177611d5212d38f52e5998115c8b8587dcfb7ddb3c4fb0da15638a0340373
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 flagged this PDF as malicious, and the heuristic firings indicate it functions as a link farm. The document body is heavily obfuscated and unreadable, suggesting it's not intended for direct user interaction but rather to host links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9924

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://lesen-und-schenken.de/userfiles/files/gamapisigajigujepi.pdf
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090b8715c27f---44355300489.pdf
    • http://afghansolar.com/userfiles/file/regufijasezirulade.pdf
    • http://collegium-connect.nl/ckupload/files/46491374856.pdf
    • https://www.cittadelmiele.it/wp-content/plugins/super-forms/uploads/php/files/6bff2c361cba86f9fb81116cc0796a1b/93656996395.pdf
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d2c641ca58e---juredutajapuzemibaluk.pdf
    • https://ost-fogging.com/upload/files/61572252413.pdf
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bb52a3cd38a---kesipigasaxasem.pdf
    • http://congluc.com/upload/files/jepafereduwawidusokakug.pdf
    • https://focaccellini.it/file/rotevezirel.pdf
    • http://axwelindia.com/uploads/71331778061.pdf
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a7bcaac52d1---nofoxakagopotok.pdf
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/b35c611b0b50c97f7118ce014d0e7ae4/dotezuvidug.pdf
    • http://aceonlinementors.com/userfiles/file/pexezilizipuzawig.pdf
    • https://fourseasons.events/wp-content/plugins/super-forms/uploads/php/files/5b838677e7a2d46f66ecbaab8adc303c/wosipatadum.pdf
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160a9dff5c2315---fowirol.pdf
    • https://lienlacanien.com/img_pages/file/73461055995.pdf
    • https://www.emma-solutions.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608367a518e13---biranekumiwujirolekes.pdf
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/36448831928a04579e5fab95c0123c0d/84692450253.pdf
    • http://ampletrekking.com/userfiles/file/gugenewomopejo.pdf
    • http://andrelandberg.com/userfiles/file/sidopulaz.pdf
    • https://too.kg/wp-content/plugins/super-forms/uploads/php/files/56f14bfe78fda13930ee9a6197ad3a23/87711281345.pdf
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/cqqkerggadhbghjs6eoj220cb0/wozokivomijotal.pdf
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b7939d3761---56802626969.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=rutina+de+abdominales+en+casa+pdf
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ec04.bin
426b466bc43e59d693e5fc537492cac657671aa7853865677e5d3e63d31abe8c
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC04 18204 bytes
font_01_sfnt_off00011a36.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A36 16792 bytes
font_02_sfnt_off00013247.bin
7d15b2d6d265aaca51dda18faee70a1b8fa9d95ed54cb111fb0895789092f9ae
pdf-font-stream PDF embedded font (sfnt) at offset 0x13247 16312 bytes
font_03_sfnt_off00014853.bin
ba1cfc03278840bfa4dd4ab4943e571d910709586d852a523af104c0e08b752e
pdf-font-stream PDF embedded font (sfnt) at offset 0x14853 10968 bytes