Malicious PDF — malware analysis report

Static analysis result for SHA-256 a83cf101882b2988…

MALICIOUS

PDF

86.6 KB Created: 2021-06-26 02:07:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b6b1f1702a3713e83f11dfde2333949a SHA-1: 982329b02d128246d37dfd32c416f4695b9e5759 SHA-256: a83cf101882b298874de2edc6ebafd561e962b7c1ae6c6ffa90f0d5ed75eb4c5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many URLs pointing to compromised CMS uploads and disposable hosting. While no scripts were explicitly extracted, the PDF structure and embedded URLs suggest an attempt to lure users to external sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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 http://gustosandvic.com/ckfinder/userfiles/files/lakiwoter.pdf
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16070bb22c9753---28821473411.pdf
    • http://fortlauderdalelimorental.net/wp-content/plugins/formcraft/file-upload/server/content/files/16072bf54c8cb0---rabomewivakef.pdf
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/plag4p6ouq6b68obppkka5qm35/58140593813.pdf
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b3eea52a53d---vekozidoxulivirudatid.pdf
    • https://islandsvefir.is/wp-content/plugins/super-forms/uploads/php/files/ugm5m75i31lal8ecqsdg10jnb1/kotomukuzodase.pdf
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/160cbdf6866bb8---59992053874.pdf
    • https://www.kiakaha.gr/wp-content/plugins/super-forms/uploads/php/files/99jv7ju7jhjse98vl8qvet4t2u/89739341516.pdf
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/1609dac2234e15---jaxobipijitize.pdf
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/1607a3beab9d44---nikewatoxedaxa.pdf
    • http://rosniyom.com/userfiles/files/sumujaz.pdf
    • http://toyotaquangninh.org/data/dulieu/files/xirulufimobetepetemotomoj.pdf
    • http://malbreil.com/userfiles/file/gegolagu.pdf
    • http://synthecinter.com/userfiles/files/mumetudowelizep.pdf
    • https://www.hdcorp.com.br/wp-content/plugins/super-forms/uploads/php/files/9il40f2jjd85qurvdivnqoe326/nunolinojawudiz.pdf
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/lhr22l07b4d1500ut79567obf6/xesirik.pdf
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/f8qq15vdju4r17nouedp59i7ts/67689107689.pdf
    • http://africanhairbraidingsalon.com/userfiles/file/lotekesugukabonumaji.pdf
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/bc3ff3a9ec17ba7ea43af3a3b7e5f5fe/41921950815.pdf
    • http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608daf52c8066---15352181107.pdf
    • https://diaspoassur.com/wp-content/plugins/super-forms/uploads/php/files/6bc7bf2dee509de9fab0b681896b74f8/lojusepijopomow.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=two+cats+talking+to+each+other
    • 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_off0000f059.bin
49d1678408b0922e7a40cd4b4e1e8d7bfdd87b13e4aa4d405398083f6fb47c21
pdf-font-stream PDF embedded font (sfnt) at offset 0xF059 10648 bytes
font_01_sfnt_off000108c2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x108C2 16792 bytes
font_02_sfnt_off000120d4.bin
57023c776d956273d13f3e4ffbfac5ae952df9613819d8efae4802ff1d029635
pdf-font-stream PDF embedded font (sfnt) at offset 0x120D4 17092 bytes