Malicious PDF — malware analysis report

Static analysis result for SHA-256 b62558b8f6ff6ff1…

MALICIOUS

PDF

75.4 KB Created: 2021-09-03 01:32:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 7a9211f6d14ccaa9fcd7310c9e8977a0 SHA-1: 249026d52ae19a192c6547d310b1eed8a4f176cb SHA-256: b62558b8f6ff6ff177a8a19f584afd4bb32a120070cc1197fe4d3e238aa812ee
156 Risk Score

Malware Insights

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

The PDF contains multiple heuristics indicating it is a link farm and a phishing lure, specifically mentioning 'job timesheet pdf' in one URL. The ML classifier and ClamAV detection strongly suggest malicious intent. The embedded URLs point to compromised WordPress sites, likely serving as a distribution point for a second-stage payload, which is a common tactic for phishing and malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://philabc.ru/uplcv?utm_term=job+timesheet+pdf PDF link annotation
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5e8fc377e---67039200999.pdfIn PDF document text
    • http://www.leasebridge.com/CKUPimg/files/11174260796.pdfIn PDF document text
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/1607e66f0bd350---71420375540.pdfIn PDF document text
    • https://www.colline-eternelle.com/ckfinder/userfiles/files/1903222943.pdfIn PDF document text
    • http://school15-tyumen.ru/f/72802990208.pdfIn PDF document text
    • http://auksozvynas.lt/userfiles/file/zaxesowixegejumokuxi.pdfIn PDF document text
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/160798b5d11570---75782928624.pdfIn PDF document text
    • http://adoriantarla.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608738d609d50---sibenazulafujidogexevavar.pdfIn PDF document text
    • http://skupka54.ru/upload/m/64814630887.pdfIn PDF document text
    • http://sjhrz.com/images/upload/File/wowem.pdfIn PDF document text
    • http://el-master.ru/userfiles/file/13633230442.pdfIn PDF document text
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b66872837e9---moligufokup.pdfIn PDF document text
    • https://kaimano.it/file/36416793295.pdfIn PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/im2iouapfnugcifujnerha7ub5/99856780778.pdfIn PDF document text
    • http://beachfirebrands.com/userfiles/file/tijapi.pdfIn PDF document text
    • https://www.bevillelecomte.com/ckfinder/userfiles/files/geriguse.pdfIn PDF document text
    • http://sad-azov.ru/wp-content/plugins/super-forms/uploads/php/files/ca105eced24c584a71b4efa64eb59807/95033427210.pdfIn PDF document text
    • http://acecaalcoy.com/userfiles/file/mazilomugujotafose.pdfIn PDF document text
    • http://ty-universe.com/image/files/20210608_124516.pdfIn PDF document text
    • https://s-serviss.lv/userfiles/file/gitotado.pdfIn PDF document text
    • https://martabaktelor.com/contents//files/72381177249.pdfIn PDF document text
    • http://patriabrno.cz/userfiles/files/xorogez.pdfIn PDF document text
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/b64b1065c2a5b00859fecfc3c500b924/89075295247.pdfIn PDF document text
    • http://ersatzmonitor.de/userfiles/file/69730712334.pdfIn PDF document text
    • http://kentcliffordreunion.com/clients/a/aa/aa84b18e55fac3ff3c25336c5005d9e5/File/xarutuxetobifalodoxif.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_off0000c852.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC852 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e064.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE064 15740 bytes
SHA-256: 690979ec5b2866593bb46a2e13b5d40728a9eb6ba8f7403b82610441febed8d6
font_02_sfnt_off00010842.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10842 10484 bytes
SHA-256: de6aa8b9437b96e001b23cdb3ed4af13303f324b20da2eff3eb8d55119a4105d