Malicious PDF — malware analysis report

Static analysis result for SHA-256 8819b2d9e62857ba…

MALICIOUS

PDF

91.4 KB Created: 2021-07-03 16:42:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 290b55000689aa441a3e2a240d2284d2 SHA-1: a06305b677b891ebf76bc1921dea0a6bbd493b1d SHA-256: 8819b2d9e62857ba4a89ee670de5b79bf59bbebc483155e78e5a2c45fa79d32e
156 Risk Score

Malware Insights

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

The sample is a PDF file flagged by ClamAV as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple compromised WordPress upload directories and disposable hosting sites. The ML classifier also strongly suggests malicious intent. The primary purpose appears to be redirecting users to potentially malicious external content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://www.asap-recruitment.net/upload/file/xetiguzemelosej.pdf In PDF document text
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b06d03df52d---32130973599.pdfIn PDF document text
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/160afb70226447---bowurumakuxatuxetinisu.pdfIn PDF document text
    • https://alkhairi.co.uk/wp-content/plugins/super-forms/uploads/php/files/f87e208b2f51eab88daa5e442c02a628/76109899930.pdfIn PDF document text
    • http://webinaris.biz/ckfinder/userfiles/publics/files/22493403916.pdfIn PDF document text
    • http://abwlargo.com/uploads/files/16673527309.pdfIn PDF document text
    • https://bonpetsupply.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607714ed08731---94813785119.pdfIn PDF document text
    • https://howardsteeves.com/wp-content/plugins/super-forms/uploads/php/files/372fbbdae9d5f6eff934a5ce87a1a0fb/bedetuzapagukizedokikaz.pdfIn PDF document text
    • http://www.maarsehoveniers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c9d94e96eae---nopivowasuwuzakibemu.pdfIn PDF document text
    • https://valleyrestoration.net/home/apf/public_html/ckfinder/userfiles/files/xujemivovokutovixone.pdfIn PDF document text
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e1d7dd8cc1---18143299119.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e6e6ec2451---18117636763.pdfIn PDF document text
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/160972ff89a6b1---japawise.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1609f8b4f9e357---64285239695.pdfIn PDF document text
    • https://lawina-radom.pl/files/file/31241070224.pdfIn PDF document text
    • http://boldogelet.hu/media/julojizej.pdfIn PDF document text
    • https://immobilgold.com/file/fatemosukejavewufiwedex.pdfIn PDF document text
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074729632d4e---96366990925.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/ccb7f59bead34ba99f4a1a06f4ddbacb/nokew.pdfIn PDF document text
    • http://altinay-law.com/images/file/selovogazazasawujimuwe.pdfIn PDF document text
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099fe8b05daa---kobelatenapojulid.pdfIn PDF document text
    • https://www.ideaklinik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071298e06057---25125842457.pdfIn PDF document text
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/afa7e47ebeb4b72e7cfcde5150d8ac41/5465693132.pdfIn PDF document text
    • http://alnoorcity.com/userfiles/file/giwojexajizogem.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=scripture+about+praying+togetherPDF 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_off00010345.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10345 16384 bytes
SHA-256: 24c1ab8693f44ffec08552e85b22ea316f0658893e1669220e9c1691724d84cf
font_01_sfnt_off00012dc4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DC4 10868 bytes
SHA-256: 2eed842d96ddec3945a0b25f31f68341e6d718338cb17d46373eb39eeec35caf
font_02_sfnt_off000146a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x146A6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1