Malicious PDF — malware analysis report

Static analysis result for SHA-256 9f8a632f0fc05bf3…

MALICIOUS

PDF

109.2 KB Created: 2021-06-27 19:58:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 0b0e5f6fb845645104ce589208453c54 SHA-1: b59397802276104c849e378ff46630e6e243fa22 SHA-256: 9f8a632f0fc05bf39d27a690a13dcd715f2ccb5797415a7a1c822d17c2de3ec2
156 Risk Score

Malware Insights

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

The PDF contains a link farm hosted on disposable domains, a common technique for SEO poisoning or phishing campaigns. ClamAV detected this file as Pdf.Phishing.Trojan, and ML classifiers also flagged it as malicious. The presence of multiple links to potentially compromised WordPress upload directories further supports a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://myhoorayhealth.com/wp-content/plugins/super-forms/uploads/php/files/7n0j2k5meecek95p3g1o4ttus7/nuroxumupitosisipin.pdf In PDF document text
    • https://nasselgrundet.se/anvandarbilder/156/files/juvatijapulivavekitu.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160b7d59c8868e---87737508034.pdfIn PDF document text
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/2ca623a515059c55f1e315a53a40156e/fadigawajadod.pdfIn PDF document text
    • http://candientuvibra.com/images/file/kudasemojireka.pdfIn PDF document text
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607d12e160c9f---19935415365.pdfIn PDF document text
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1606f3edb536d7---75732883628.pdfIn PDF document text
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a250aa3f591---6857441582.pdfIn PDF document text
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/160928d5dee0bf---zutukisi.pdfIn PDF document text
    • https://elitestrategyglobal.com/wp-content/plugins/super-forms/uploads/php/files/ee9068e75674891d7a602dbf5f70fbe2/29590593633.pdfIn PDF document text
    • http://gancza.pl/userfiles/file/dorisozawigipepazaz.pdfIn PDF document text
    • https://syntellect.ru/Repository/file/50862620509.pdfIn PDF document text
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/cab630f2582a2211ebe723764151a251/zoluvapizimanamewaw.pdfIn PDF document text
    • https://skazkavdom.com/wp-content/plugins/super-forms/uploads/php/files/75f881e4be6c878438e3baf072ce4ec3/giniruto.pdfIn PDF document text
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/4112be72a19bc91ea449d8302fa78e15/lisutut.pdfIn PDF document text
    • http://npas.ru/pic/file/laworesununodape.pdfIn PDF document text
    • https://atlanthealth.com/wp-content/plugins/super-forms/uploads/php/files/eebdbb5e3416c49960eee0401b9b51ac/35911755622.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089223ded16c---10916343793.pdfIn PDF document text
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be9e3cdde1f---kokumojavefujewuretujeve.pdfIn PDF document text
    • https://gservicepz.com/wp-content/plugins/super-forms/uploads/php/files/8270a4f716931995e3a53aa57ac62eaf/6035823737.pdfIn PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/c7face3b5c5c60580c9814d440d5fc08/joroful.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/160796fd8ef950---80819075756.pdfIn PDF document text
    • http://kochamsushi.pl/UserFiles/file/85801296620.pdfIn PDF document text
    • http://cateringkieuan.com/uploads/userfiles/file/92844230370.pdfIn PDF document text
    • http://dragoniresorts.com/userfiles/66880742699.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=rotary+internal+combustion+enginePDF 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_off000146b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x146B5 10972 bytes
SHA-256: c8f0778ad082c16cc020f6b2729c0c26e20445669655b9c1800f998cd70bec57
font_01_sfnt_off00016035.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16035 18436 bytes
SHA-256: c14f9ae8418d98e935f8fdf6cc99da4ee46e32f68f66f6571e6f52c4c79eff76
font_02_sfnt_off00018f3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18F3D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1