Malicious PDF — malware analysis report

Static analysis result for SHA-256 fcf8393868113267…

MALICIOUS

PDF

74.3 KB Created: 2021-07-13 02:37:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 61fc6946035285035baf3c2b4e8405db SHA-1: 1970ecee7f79be66ea2db07b13dc65f314793f87 SHA-256: fcf83938681132673bec0cb9c25e7a39ab7fa03dfa629efe239dab43d1628e66
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to compromised WordPress sites and disposable domains, indicating a link farm designed to lure users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. While no scripts were explicitly extracted, the nature of the URLs and the heuristic firings point towards a phishing or credential harvesting attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://synerhu.ru/uplcv?utm_term=introduction+to+operations+research+7th+edition+solution+manual+pdf PDF link annotation
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/4ca76a17156c5278787f62b251e0464f/fifesijuguziwiporelajatan.pdfIn PDF document text
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a36c919bb1b---54798584624.pdfIn PDF document text
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a241831982c---51550779227.pdfIn PDF document text
    • http://bluedevils59.com/clients/862365/File/tilejawizegikozuxuga.pdfIn PDF document text
    • https://xn----7sbabak5acz7byau.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/49d83085aefea65023cb2bcccdee6e3b/paxekipunedibi.pdfIn PDF document text
    • http://dahchen.tw/userfiles/file/34989819524.pdfIn PDF document text
    • https://pilotcenter.gr/wp-content/plugins/super-forms/uploads/php/files/dkhcg6ep392anvpnleamac06go/legumibexepoluwutegamo.pdfIn PDF document text
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160757fffd44eb---4025523553.pdfIn PDF document text
    • http://3bbb.fr/ckeditor/upload/files/zutapikan.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/hcotoe9ib5eqp58d9ae8pvrnce/jipomapax.pdfIn PDF document text
    • https://conexkarvan.com/cache/fck_files/file/fororewun.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160e71a58a2af1---69443603962.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084ace915ec4---ritabowitebu.pdfIn PDF document text
    • https://terminal.hr/userfiles/file/11985354179.pdfIn PDF document text
    • https://angelsstaff.com/uploads/file/ziserifonimizevi.pdfIn PDF document text
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9042a59fd---7890898940.pdfIn PDF document text
    • http://otvorene-srdce.sk/userfiles/file/84826273308.pdfIn PDF document text
    • 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_off0000bf78.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF78 10988 bytes
SHA-256: 19d4d114f9cbbd161ec574094438af1b3dd14495e1df7eb9b25a5eca9d7d25b4
font_01_sfnt_off0000d8ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8CE 16464 bytes
SHA-256: b2d87029469b667c35cc071cdb7546c18df091bb2f7f98e893a058b314cb846a
font_02_sfnt_off000103d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103D4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1