Malicious PDF — malware analysis report

Static analysis result for SHA-256 d1f853c5cfe7deed…

MALICIOUS

PDF

72.9 KB Created: 2021-07-04 06:31:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-17
MD5: 42eb513b70fba55666f984a0c01c5996 SHA-1: e33db63af90e5e1583ba54715c09e8d960c4ee36 SHA-256: d1f853c5cfe7deedc4ca1c6bc2cb3cafa9c8142d5d183e2129fe118a24f46730
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised WordPress upload directories and other disposable hosting, suggesting it functions as a link farm to distribute malicious content or phish users. The presence of embedded URLs and the PDF structure itself are indicative of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607d60c2bf07d---80162577303.pdf In PDF document text
    • https://alkhairi.co.uk/wp-content/plugins/super-forms/uploads/php/files/05ddc4cff48a427c8d7562efe7e2c113/zaturovus.pdfIn PDF document text
    • http://www.jimenez-casquet.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607220ef1e2dc---kavad.pdfIn PDF document text
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1608256cc9775f---41338139812.pdfIn PDF document text
    • http://stpatricksreunion.com/clients/84553/File/81454264072.pdfIn PDF document text
    • http://arniestribu.com/campannas/file/tadipaboxesemu.pdfIn PDF document text
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a44d8d89c4a---93651073595.pdfIn PDF document text
    • http://bestbelly.org/content/files/files/35237642496.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/c823bd92500f2ff5fbf19d8db88cc0ac/newudezemavulukefi.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a85abbed9ae---27538468599.pdfIn PDF document text
    • http://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f9b4bdaa7d---meliranar.pdfIn PDF document text
    • http://www.suffaheducation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082d2ffbf1d8---wojukakefemosexiwu.pdfIn PDF document text
    • https://sip7.pl/autoinstalator/sip7.online/wp-content/plugins/super-forms/uploads/php/files/bff2581bf17860f1dc7764ccc3707006/57398583227.pdfIn PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/2844e9e39e8b12f062bff28defa0c8ba/79544282905.pdfIn PDF document text
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073c72cce048---kikawepudovijek.pdfIn PDF document text
    • http://tfforming.ru/d/files/40651123402.pdfIn PDF document text
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/160c8b04e58dab---wagosolagi.pdfIn PDF document text
    • https://forex-robo.org/wp-content/plugins/super-forms/uploads/php/files/697a5a955e601ce1398ce40f4c4dd3e6/75598774961.pdfIn PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a777bf41de0---tideseberamobezeme.pdfIn PDF document text
    • http://ottotech.center/userfiles/file/jixalido.pdfIn PDF document text
    • http://bazatalty.pl/wp-content/plugins/super-forms/uploads/php/files/7c2cb77922634419d110b0faf007f0dc/momapep.pdfIn PDF document text
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/cf8143de2f681c18a17ceb779c53e3a8/17943230953.pdfIn PDF document text
    • http://rocb-ap.org/file_media/file_image/file/jopedenuxul.pdfIn PDF document text
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/724fc1ded11e6f5f4ff53129065fed5a/50210273037.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=new+english+file+intermediate+student%27s+book+keyPDF 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_off0000b9d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB9D6 11344 bytes
SHA-256: a27fc2fa4fe380015ad853b5b321c478b55c607266721c93c6f8e18a4f769858
font_01_sfnt_off0000d437.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD437 16284 bytes
SHA-256: 09aaf161cf4fe331d1aafef5d6d808569107619521db7758d4e440773b5dad18
font_02_sfnt_off0000fdc3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDC3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1