Malicious PDF — malware analysis report

Static analysis result for SHA-256 674a4efc4d5c4406…

MALICIOUS

PDF

85.8 KB Created: 2021-07-07 21:48:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cf699d5ce7338f9b3be68b530da5284f SHA-1: 11fc4cd658e61155419d2ed8a5afc0f9b3e7483c SHA-256: 674a4efc4d5c4406288353a48b1ec75a4ad3830f89eb0392b9b98a16290ff291
96 Risk Score

Malware Insights

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

The ML classifier strongly indicated maliciousness, and the PDF contains a link farm pointing to numerous compromised WordPress upload directories. These links likely serve as a distribution mechanism for further malicious content, potentially exploiting vulnerabilities in PDF viewers.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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://fenixfalt.com/userfiles/file/kiwowubatololujixomowaji.pdf
    • https://beribuket.ru/wp-content/plugins/super-forms/uploads/php/files/0c339d7792d0fa6f083de9dd3096c29c/zebofixuradiwut.pdf
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e01804f060d---paxogas.pdf
    • https://tkpmission.org/wp-content/plugins/formcraft/file-upload/server/content/files/160db018447ad9---1682258007.pdf
    • http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/pq2u9q9sg4dlve00ojmadlmse3/fijuvutuxotaj.pdf
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f230662dcd---xisafuxotobizasa.pdf
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/160818e29c0d17---sosirolutodalaxegufenebez.pdf
    • https://kvkumariajnkvv.org/singhania/downloads/file/46375465750.pdf
    • https://elpmarketing.ca/wp-content/plugins/super-forms/uploads/php/files/c8aad20721fec4e885f74266a947c49c/dedesogetajufokubeji.pdf
    • http://cleannshieldflorida.com/wp-content/plugins/super-forms/uploads/php/files/c2d5d16824db23217d40f7ab904e10a2/wamoxe.pdf
    • https://morabia.fi/images/file/56339568120.pdf
    • http://gayaarchi.com/userfiles/file/20210628184809.pdf
    • http://cec-intl.ru/app/webroot/files/file/75464959180.pdf
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a1066e22b8a---22498162881.pdf
    • https://g3az.com/wp-content/plugins/formcraft/file-upload/server/content/files/160850321677c0---73338662327.pdf
    • https://accuratesearch.com/userfiles/file/vuxerotuz.pdf
    • https://www.sanier.pl/wp-content/plugins/super-forms/uploads/php/files/fo2ec6toqf0v1hvcg6ah4dnsst/14053897851.pdf
    • http://aceonlinementors.com/userfiles/file/54951300558.pdf
    • http://www.gaviprintpack.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bffa5590bdc---wuvokutoxijur.pdf
    • https://cremeconferences.com/wp-content/plugins/super-forms/uploads/php/files/172e1373500b62e4ffa9e2b713003771/lilunigozijojeg.pdf
    • https://accesoriosalmayor.com/images/userfiles/file/jimidomumawazisinozewo.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=6+is+what+percent+of+8
    • 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_off0000e9e4.bin
cb96110180c796c0926acffadc05351bb22be8fb7ad7f319537ac29a5d1848ff
pdf-font-stream PDF embedded font (sfnt) at offset 0xE9E4 10896 bytes
font_01_sfnt_off00010329.bin
12120f9f3abe1cc41567d3181b867a51783e5d426487bf17be02c32c42d3fff0
pdf-font-stream PDF embedded font (sfnt) at offset 0x10329 17844 bytes
font_02_sfnt_off00013242.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13242 16792 bytes