Malicious PDF — malware analysis report

Static analysis result for SHA-256 4caebc079cb4df98…

MALICIOUS

PDF

74.9 KB Created: 2021-09-20 19:31:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 1c4a1cd031e62ebafa1707dd8fb32634 SHA-1: bfdea00894483c5966cef8b194398636155412e0 SHA-256: 4caebc079cb4df98276f9a39f75e51ef5e1750443cc057d22a8a5c2130e088f5
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites acting as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The presence of external URI heuristics and compromised CMS upload links further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://archism.ru/uplcv?utm_term=android+aes+256+encrypt+decrypt+example PDF link annotation
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/161447c9c513ce---70386549217.pdfIn PDF document text
    • https://polymadeniyaglar.com/fckeditor/userfiles/file/zafupamenugapezelikamani.pdfIn PDF document text
    • https://insinkerator.us/images/uploaded/file/48623053248.pdfIn PDF document text
    • http://abdon.madteam.net/ckfinder/userfiles/files/39064457456.pdfIn PDF document text
    • http://akvari-um.ru/userfiles/file/guwozone.pdfIn PDF document text
    • http://renovfab-menuiserie.com/userfiles/file/lerufit.pdfIn PDF document text
    • http://evopizza.lt/ckfinder/userfiles/files/wedisodovuwawiwotunibi.pdfIn PDF document text
    • http://infunplastic.com/d/files/xopupopoxefotirirazorepa.pdfIn PDF document text
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/161406f8fbb1b6---630933371.pdfIn PDF document text
    • http://intersonik.eu/upload/files/74746234575.pdfIn PDF document text
    • https://alicantea.centralcms.cloud/galeria/files/pepofifajogiduz.pdfIn PDF document text
    • https://bluza-shop.ru/content/File/vulijoduzusapo.pdfIn PDF document text
    • https://sasalidayanisma.org/uploads/file/tezotasulanuvuxudoso.pdfIn PDF document text
    • https://socialacademy.gr/wp-content/plugins/super-forms/uploads/php/files/f0936f017a9a975f2928978ccda7ce1e/97985722429.pdfIn PDF document text
    • https://aglogistics-bo.net/userfiles/file/91532819865.pdfIn PDF document text
    • http://eg-connect.com/uploads/editorfiles/file///24920376869.pdfIn PDF document text
    • https://mannoorpally.com/uploads/file/rebalabo.pdfIn PDF document text
    • https://thietbivesinhanhhuy.com/asset/files/37449193044.pdfIn PDF document text
    • http://nationalherbo.com/userfiles/file/giwuniralizaxobixulox.pdfIn PDF document text
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/e75a39b65d8605c13ed30d3f0b3bdf4c/fagudiguf.pdfIn PDF document text
    • http://receptlap.hu/files/suvuvuzatogogarukulimuz.pdfIn PDF document text
    • https://sealand-pptc.com/userfiles/file/26618337033.pdfIn PDF document text
    • http://fanta-life.com/userfiles/file/29448734099.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_off0000bf25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF25 17056 bytes
SHA-256: 59715d70b352898f43f031b1014046e9a2d4baaaee93ce44b5a8c1c64740700f
font_01_sfnt_off0000eb5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB5E 11292 bytes
SHA-256: 2a60a61f661a44e2518fd5ea38fd099c17c743f5a3eceedbb34884764ae04226
font_02_sfnt_off00010606.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10606 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1