Malicious PDF — malware analysis report

Static analysis result for SHA-256 53bf2456a483cc70…

MALICIOUS

PDF

88.2 KB Created: 2021-06-27 05:30:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 67584fc79e979d656200d77e3b256c4a SHA-1: e2d986f14f48ec96ee3063f9e1aedf6a8b1c6b84 SHA-256: 53bf2456a483cc70f7a395e15b63a266e30501b6dcd089131babf039e895416d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains a link farm pointing to multiple compromised WordPress upload directories, suggesting an attempt to host and distribute malicious payloads. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics indicates a deliberate effort to obscure the true destination of the links. No scripts were extracted from this sample, but the structure strongly suggests a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://centrosteadycam.it/wp-content/plugins/super-forms/uploads/php/files/44cbbd51125b414839391ad280ead876/91584067368.pdf
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160c09dcb9531f---fupilik.pdf
    • https://inchiriereelicoptere.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b5e5791e17f---87325348040.pdf
    • https://suma.ca/upload/editor/file/doxekopesewewisoxoji.pdf
    • https://purebodycare.courses/wp-content/plugins/super-forms/uploads/php/files/2kmulcd9rab8a6dvuqltp6u9j0/suwipuviremolafesofom.pdf
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/a2ce8e3350f4aa69f214ad37136b0451/78652182106.pdf
    • https://primewestelectrical.com/wp-content/plugins/super-forms/uploads/php/files/940f0c9ef736c5a30ad378026cac5079/dosezuzu.pdf
    • http://timebank.ru/sites/default/files/photos/pagefile/3167379467.pdf
    • https://outsourcedbackoffice.co.uk/wp-content/plugins/super-forms/uploads/php/files/a15123c42bf5c8ab5d4edab9ae2fa15e/tevapoduvolofax.pdf
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086fffde0c8c---jowibefinowuni.pdf
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608daaee9514f---7366351425.pdf
    • http://danielbushreunion.com/clients/41596/File/45111774387.pdf
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160afb6c4df42a---bebamerimoxedubumezozedo.pdf
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1608f111dcb772---porajagusumatijuzavu.pdf
    • http://zuche0551.com/upload/file/mozuxuseresazififazosir.pdf
    • http://themultifold.com/wp-content/plugins/super-forms/uploads/php/files/spmvuuievt57f6hqomjaovkmu1/15438244332.pdf
    • http://svenstavik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ff1405b4c3---78164728555.pdf
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607560deab64b---zawodowupaxamukasuve.pdf
    • https://www.hediyevideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081c7aa27dad---ronasiw.pdf
    • https://www.chartsunlimited.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7f4006f26---33768123326.pdf
    • https://diversified-nj.com/wp-content/plugins/super-forms/uploads/php/files/fdbb463fe807af2960e2d3dfa5d2634e/bilifopiwusonodagij.pdf
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4b605d36e1---24084923470.pdf
    • http://www.stallionreadymix.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160bf58e313c9b---zetisawuvuwuz.pdf
    • https://mrmusicfoundation.org/wp-content/plugins/super-forms/uploads/php/files/ngljkeatkmnpramvpvmvgu5c7s/69650827939.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=signs+and+symptoms+of+dehydration+nursing
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f797.bin
ad7fb2bfa2edc5508bada9353b3c64382b1f1d67d724cd257e4cdced977f923d
pdf-font-stream PDF embedded font (sfnt) at offset 0xF797 16264 bytes
font_01_sfnt_off000121b0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x121B0 16792 bytes
font_02_sfnt_off000139c7.bin
19042458ed91e58e2db4b319ad8b477a710e715f33aa1a4be478989df17a67d9
pdf-font-stream PDF embedded font (sfnt) at offset 0x139C7 11188 bytes