Malicious PDF — malware analysis report

Static analysis result for SHA-256 55784f3619883112…

MALICIOUS

PDF

95.2 KB Created: 2021-06-30 19:13:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 5953881b8ee26bb7fdc1047888781c8f SHA-1: a1c2836c7cf7b32d0c115f27e68ec99ae621de7f SHA-256: 55784f3619883112748a2bb01211625225b35ff57c949eb8d5d235acc1012650
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. Numerous heuristics indicate the PDF contains a link farm pointing to compromised WordPress sites and disposable hosting, likely to redirect users to malicious content. The embedded URLs and the nature of the heuristics strongly suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a92fdc90da5---remikasumirusejadukeziwow.pdf In PDF document text
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c23da9f1ba6---rotufikabinukonuvodixeme.pdfIn PDF document text
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/pisekajefusotevup.pdfIn PDF document text
    • http://apexibd.com/uploads/fck_uploads/file/gutulepusivubobig.pdfIn PDF document text
    • https://rclurie.com/wp-content/plugins/super-forms/uploads/php/files/925c75121e515478c25137634855d963/43048732019.pdfIn PDF document text
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/16099d1d5b09d6---81219693530.pdfIn PDF document text
    • https://teenvolunteerdallas.org/wp-content/plugins/super-forms/uploads/php/files/1358edd73fa6e008d3f9adf447d3d648/zetineluweneluduseru.pdfIn PDF document text
    • https://festivalecolo.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160bcfe502588f---52005420775.pdfIn PDF document text
    • http://sjar-tech.com/uploadfile/file///2021051719471273.pdfIn PDF document text
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aea54b3c87d---kikufulipipapela.pdfIn PDF document text
    • http://payassistinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609830ccb1d25---72746047683.pdfIn PDF document text
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/gkst9ahvhsqoi7nsjimafq292i/visererapuv.pdfIn PDF document text
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae773065b73---80433022330.pdfIn PDF document text
    • http://akkoryazilim.com/userfiles/file/dedomedisezi.pdfIn PDF document text
    • https://moma-restaurant.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ca38ee36263---46338632310.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/7bj3spgab3sv09f04h4mhluum2/witewodawux.pdfIn PDF document text
    • http://79.170.40.182/boothtastic.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dc07dc08d5b---25587256604.pdfPDF link annotation
    • http://fresh-j.info/images/uploadedimages/file/83254726509.pdfIn PDF document text
    • http://immodraft.nrw/images/architekten_agentur_images_/file/mijefewosokuv.pdfIn PDF document text
    • https://pensiuneavalentina.ro/app/webroot/file/9538704859.pdfIn PDF document text
    • https://daaeportrett.no/upload/file/tujafoxix.pdfIn PDF document text
    • https://www.sevgiliyevideo.net/wp-content/plugins/formcraft/file-upload/server/content/files/160858b8db135f---fuluwupukosiwiburi.pdfIn PDF document text
    • http://workprohealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/160857646ae4e6---tedevuguridijuweni.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=full+form+of+thf+in+organic+chemistryPDF 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_off00010ca1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CA1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000124b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124B8 10972 bytes
SHA-256: 87369b8faa2c779b5fef42790d4453ea1eec0f94362de3502d293019cf8f963b
font_02_sfnt_off00013e0c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13E0C 18712 bytes
SHA-256: 156ab18d0eb2673d9c230e008b5b9a4baf2c5e488215ecaaaf5b54123cae3305