Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b4a9d2797f7f529…

MALICIOUS

PDF

74.1 KB Created: 2021-09-06 15:09:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e666853a0a6968c0a0852ef86a289a49 SHA-1: ff45176543d8b13cbc5b41a9c8c9ac09acb11c4c SHA-256: 8b4a9d2797f7f52963f30dbce83011f461dfce30fc94afb74aaabfe0de0e65b3
96 Risk Score

Malware Insights

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

The PDF document contains a link farm pointing to multiple distinct hosts, many of which are hosted on compromised WordPress installations. The ML classifier strongly indicated maliciousness, and the structure suggests an attempt to lure users to external sites, likely for further exploitation or phishing. No scripts were extracted, but the PDF structure itself is indicative of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cdcb9de00fb---61036460753.pdf
    • https://janeunchained.com/wp-content/plugins/super-forms/uploads/php/files/lapuc6aupmajndpo3gc4bfmb3f/84895951328.pdf
    • http://haustechnik-hagenauer.at/11966002806.pdf
    • http://ned.ru/uploads/files/nubozafureb.pdf
    • http://files.ibiza-ferien.de/file/98772905543.pdf
    • https://islandsvefir.is/wp-content/plugins/super-forms/uploads/php/files/higukvqfq20mr1qvu8cgk9jhic/42740248695.pdf
    • https://hmradiatoriai.lt/images/files/87409332935.pdf
    • http://allnatureint.com/userfiles/file/41558334373.pdf
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/a79d29c0ca3332ac056930219fef18ef/49255978839.pdf
    • https://bluebeakbranding.com/wp-content/plugins/super-forms/uploads/php/files/6f630d90796785f0e566b373a01b884e/dupiw.pdf
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a492289c123---vajoginob.pdf
    • http://kuehllawpc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/87828439200.pdf
    • http://cuadepthanglong.com/images/ckeditor/files/8120994255.pdf
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/d7dc12a12a6b6fca45b1d12974b2d5d8/magutato.pdf
    • https://ketex.com/trcgp/ckfinder/userfiles/files/nodesukomakoraxab.pdf
    • http://fotografoenricogiampieri.it/userfiles/files/jikesupega.pdf
    • http://xuanfe.com/uploads/FCKeditor/file/91272399878.pdf
    • http://handbook.hu/upload/page/file/59221765550.pdf
    • https://hacunamatata.ru/wp-content/plugins/super-forms/uploads/php/files/3e30283201d79004812e443ef167efca/65314268735.pdf
    • https://classykitchen.pl/web/uploads/files/mefetesajixitamis.pdf
    • http://casaatlantida.com/userfiles/file///23847287615.pdf
    • http://abwingssuffolk1.com/uploads/files/xugora.pdf
    • https://kozhikodedeaf.org/admin/my_files/file/tasopav.pdf
    • http://hermangroupcorp.com/clients/3/38/389628ddbd62db2fa1e4299ecdfc1861/File/39603553075.pdf
    • http://fongyoskert.hu/userfiles/files/77531417577.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=l%C3%A1minas+de+la+c%C3%A1tedra+de+paleograf%C3%ADa+y+diplom%C3%A1tica+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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b776.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB776 16792 bytes
font_01_sfnt_off0000cf8d.bin
9a05b776107f237f91d4b403768ff7e35c73134d4f56b89e7500b9a6e3601051
pdf-font-stream PDF embedded font (sfnt) at offset 0xCF8D 11276 bytes
font_02_sfnt_off0000e94b.bin
bd773cb833e618ce5f65d106179a2f422d11afbb5c721dd34dc397c471c9ecf7
pdf-font-stream PDF embedded font (sfnt) at offset 0xE94B 18220 bytes