Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd9e5b16ff346233…

MALICIOUS

PDF

82.7 KB Created: 2021-06-25 20:21:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 21f1aa45d995c574b3bd9e4bb34b6359 SHA-1: fa87ffffac1c8fedc75736acf989fbfda8a99cc0 SHA-256: cd9e5b16ff3462337fd2350d3f374256e80e532dba8cd51ac3d80f276652f5e2
156 Risk Score

Malware Insights

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

The sample is a PDF file identified as malicious by ML classifiers and ClamAV. It functions as a link farm, with numerous URLs pointing to compromised WordPress sites. These links likely serve as a distribution mechanism for further malicious content or phishing attempts. No scripts were extracted, and the document body was unreadable, limiting deeper analysis of the specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160c73f3bdbeea---penanamaduzoba.pdf
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16089103cb01b4---52334553598.pdf
    • http://seyrimerdin.com/userfiles/file/38494681558.pdf
    • http://ibiforstarlight.org/clients/3/3c/3cfcca4e360ca8807b7dd7d6e7cbeae0/File/88002055756.pdf
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b33b5f12bd---98293990810.pdf
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a150a0a4312---9508735641.pdf
    • https://incoyun.com/calisma2/files/uploads/ruganujerelovunifinozaj.pdf
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/be70a521febb85696ec1bf48579d1d68/38156686877.pdf
    • http://piazzademarini3ge.com/userfiles/files/89002347062.pdf
    • https://www.justgym.co.za/wp-content/plugins/super-forms/uploads/php/files/6pdrcvdmep2qs340bifc3jtqpn/28299142590.pdf
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a77d0392b63---97964752833.pdf
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/rfs0iorso8iufl3usm3railk74/58322309903.pdf
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16077a170cba9d---rufafowipaxelevu.pdf
    • http://fvv-hohenfelde.de/sites/default/files/files/fexiladapi.pdf
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/nv3ameq27to5118rfqtkssp505/18032286009.pdf
    • http://asokmontridental.com/userfiles/file/kuwogenepexesedev.pdf
    • https://jaunimodienos.lt/wp-content/plugins/super-forms/uploads/php/files/o33m8scc6fa2pvb6hnv2jvnp7u/riletitalabajonipewege.pdf
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8304322e8c---jetipodideduradu.pdf
    • https://wulf-sanitaer.de/wp-content/plugins/super-forms/uploads/php/files/9u05mok7p5onpouj9hturdjpe8/nerovikipixa.pdf
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/6fff32ec024e2e63c17be4f661f6d821/44544884961.pdf
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5d3c24c3a0---budogewobobemiloj.pdf
    • http://lawrence-spruill.com/clients/42275/File/bajalomesaxutujatatopivit.pdf
    • https://fonixkoncert.hu/upload/file/luxepovidudileworuvuxej.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=priest+marriage+lines
    • 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_off0000e456.bin
268982cab8a68108ff762d74bc093cfdc75ebd969f5c33a9edba7806b5b8ed14
pdf-font-stream PDF embedded font (sfnt) at offset 0xE456 10332 bytes
font_01_sfnt_off0000fb98.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB98 16792 bytes
font_02_sfnt_off000113aa.bin
0a54e1f69848b2a50fd97667469631fc00b46326a08f22045b7c8d5e39975214
pdf-font-stream PDF embedded font (sfnt) at offset 0x113AA 16320 bytes