Malicious PDF — malware analysis report

Static analysis result for SHA-256 113113eb0e5f03f5…

MALICIOUS

PDF

86.0 KB Created: 2021-07-04 03:14:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: b1365c183f1d4916123941e33c509c74 SHA-1: 32d13832266fed36e2f87d9b8faa67a8d3beb5c0 SHA-256: 113113eb0e5f03f55d974d4a332c349c47d8092437da6bd4b0195d51386b7526
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories, indicating a link farm or redirection scheme. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or SEO abuse. The presence of multiple links to potentially compromised WordPress sites and the use of UTM parameters in some URLs further support this. No scripts were extracted, and the document body was unreadable binary data.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://techsystem.gr/data/uploads/ckeditor/files/rijatiz.pdf In PDF document text
    • http://www.gaviprintpack.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cdb4a1c280---nosofagajo.pdfIn PDF document text
    • http://korsorlampang.net/user_img/files/48633963112.pdfIn PDF document text
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab387654a60---96780947279.pdfIn PDF document text
    • https://www.drserapkagan.com/wp-content/plugins/super-forms/uploads/php/files/tea8hrlgs7f00ea4rjetof9qb9/padodalazazilufusopi.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16076945dd7d3e---pemoli.pdfIn PDF document text
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a723cb92f1e---rajijozela.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a4fd3f0960---zosaton.pdfIn PDF document text
    • https://okinawa4d.com/contents//files/walugu.pdfIn PDF document text
    • http://ash-graphy.com/userfiles/file/19826037200.pdfIn PDF document text
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088af99926ef---bidibulasefosujokew.pdfIn PDF document text
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c0aa5c2ba82---4326012637.pdfIn PDF document text
    • https://aimara-bg.com/userfiles/file/dobegowotarifokixet.pdfIn PDF document text
    • http://ngpsusa.com/wp-content/plugins/super-forms/uploads/php/files/bh627j42hkqtcnn3dsvhknjse9/mezusepijuzezudutoxofaxub.pdfIn PDF document text
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160b9e9430730d---jefipikumejinujeronotux.pdfIn PDF document text
    • http://hamdard.com/hamdard/app/webroot/img/ckfinder/userfiles/files/70301791631.pdfIn PDF document text
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/3936a5555c976789b26d987a7fb49569/70431526892.pdfIn PDF document text
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/lir6193dt47nfdbf2espjuii45/56543989204.pdfIn PDF document text
    • https://www.albispanaderia.com/wp-content/plugins/super-forms/uploads/php/files/e82d38c5b21a3016bf58f58d189d7f40/witorelamagorup.pdfIn PDF document text
    • https://plswa.com/wp-content/plugins/super-forms/uploads/php/files/632e3b311601fc040f3722c1b8be09e7/rinunijifufavusarubibotuj.pdfIn PDF document text
    • http://savalis.ru/userfiles/file/94834916501.pdfIn PDF document text
    • http://fedime.org/imagenes/xogamudali.pdfIn PDF document text
    • https://www.prowallpanama.com/wp-content/plugins/super-forms/uploads/php/files/205b5c9cf3638fbbbc9d58e5c8b133d1/86877922124.pdfIn PDF document text
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160756f29e9e99---96297397178.pdfIn PDF document text
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/ab9956756279129d6cf051268faf555f/ridaberopum.pdfIn PDF document text
    • http://jtour.vn/userfiles/file/wadudozidobolosufapa.pdfIn PDF document text
    • http://es-umzuege-transporte.de/wp-content/plugins/super-forms/uploads/php/files/411717b206eebbc56a94a8de51693dae/xebitogozaba.pdfIn PDF document text
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c14ca0c758e---gojesixatasimitopojotat.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=holiday+pay+in+lieu+of+noticePDF 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_off0000ee97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE97 10552 bytes
SHA-256: cee07abe2168f203431751afcba01abdc0ae23705b8c67c5efb54321681bf3a0
font_01_sfnt_off000106b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106B4 16780 bytes
SHA-256: c0485958960d54e643752cee1480b80fb0c92a0227270af41a01be18d6f9c6c5
font_02_sfnt_off00013279.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13279 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1