Malicious PDF — malware analysis report

Static analysis result for SHA-256 0d4b8ba11eaa7815…

MALICIOUS

PDF

94.0 KB Created: 2021-06-29 08:35:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-16
MD5: 7ab6cbbb966152788a547989cf864103 SHA-1: 4dbbbe7d8368aff181b80066f5ce6b890425ae7b SHA-256: 0d4b8ba11eaa78159e5294a74673da58068f6c32979e72dd8ec881680081b378
156 Risk Score

Malware Insights

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

The sample is a PDF identified as malicious by ClamAV and an ML classifier. It functions as a link farm, containing numerous URLs pointing to other PDF files hosted on compromised WordPress sites. This suggests an attempt to manipulate search engine results or distribute further malicious content through a chain of compromised resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

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 https://southtours.com/wp-content/plugins/super-forms/uploads/php/files/pa1lff405lp52tbq8n9498gocn/dejat.pdf In PDF document text
    • http://extintoresorigen.com/images/editor/23968719855.pdfIn PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/a83615b01993da5e06b2543c2584d98f/67973225238.pdfIn PDF document text
    • http://xn--80akazwaeiw.xn--p1ai/editorfiles/file/31537233061.pdfIn PDF document text
    • http://tavernadelsnoguers.com/wp-content/plugins/super-forms/uploads/php/files/97d5588df05d6da32d3f93fe8e70fe79/diberugitiw.pdfIn PDF document text
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/51d704f1004c832ddf5883e9d64cc552/94538236977.pdfIn PDF document text
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb634678332---ledobuneraw.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9f83919bc7---28030373501.pdfIn PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/772444a9f8c5da3865f763320ac0710e/movukunozewejoguga.pdfIn PDF document text
    • https://samarpanbharat.org/trila/userfiles/file/wirogomugebewofokare.pdfIn PDF document text
    • https://asthasupermarket.com/userfiles/file/xekebunovonut.pdfIn PDF document text
    • http://blog.crowdly.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d86df8be8a---29787810920.pdfIn PDF document text
    • http://safeabortionnepal.com/userfiles/file/67468184182.pdfIn PDF document text
    • http://hkt-optics.com/hkt/images/userfiles/file/remazowajitefufowuta.pdfIn PDF document text
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1606d2e307a156---sogufarutugonafev.pdfIn PDF document text
    • http://bhs1966maui.com/clients/64750/File/parapugesobujaguge.pdfIn PDF document text
    • http://qhzs88.com/admin/fckeditor_upfiles/file/2021060813165880554.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607de28fe995d---bemovedexarijune.pdfIn PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/1608e94289a74b---wizojoto.pdfIn PDF document text
    • http://www.magicapro.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c41d22a8faf---25461256996.pdfIn PDF document text
    • http://caratow.eu/userfiles/file/dodupaluzefegovijete.pdfIn PDF document text
    • http://accu-chek-event.com/ckupload/files/wemeji.pdfIn PDF document text
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/d1b257d9f68d67fd67adb149575a6ea0/34943417748.pdfIn PDF document text
    • http://promocode.lu/userfiles/files/vowaverobifanasibuf.pdfIn PDF document text
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093fa81408cd---pogem.pdfIn PDF document text
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/0fb6b245566cc282f396b1793d1dd0b9/rifixigu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=equation+for+nuclear+decayPDF 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_off00010cff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CFF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012511.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12511 17312 bytes
SHA-256: abc5a69d9e5667c05a65fdc0e48b6044d46e53b763c52f62db61c8c854c3e126
font_02_sfnt_off00015287.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15287 10644 bytes
SHA-256: 625125cacc135df7c62763888a03c53455254b5b8612012e472e03fdf2611913