Malicious PDF — malware analysis report

Static analysis result for SHA-256 bac655972b1d69a6…

MALICIOUS

PDF

87.6 KB Created: 2021-09-07 13:18:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-16
MD5: 4a4a513ffac7d8a69329480a91b58d2e SHA-1: f7878f47d8b1dfb510f663fa6bd32ad73216b362 SHA-256: bac655972b1d69a6f621499542df571c009c067d2c31616a120fef27c3971ad4
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier indicating a high probability of maliciousness. It contains numerous links to compromised and disposable domains, suggesting a phishing or malware distribution campaign. The presence of external URIs and link farm characteristics points towards an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://catamma.ru/uplcv?utm_term=subject+pronouns+spanish+worksheet+free PDF link annotation
    • http://premiercontractinginc.com/files/file/43221328230.pdfIn PDF document text
    • http://baikalspring.ru/ckfinder/userfiles/files/93921205194.pdfIn PDF document text
    • http://mognational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090ee52f30ea---masakasonibemimeruka.pdfIn PDF document text
    • http://kd-council.com/upfile/files/17800695984.pdfIn PDF document text
    • https://olterus.com/contents//files/kerinoxotafofewipoka.pdfIn PDF document text
    • http://peaceinsrilanka.lk/userfiles/file/fegopidabanajavupametotiw.pdfIn PDF document text
    • https://dehayemek.net/upload/ckfinder/files/kufodapagobitoropujefije.pdfIn PDF document text
    • https://getlovebooks.com/wp-content/plugins/super-forms/uploads/php/files/c9572ea1a922d540d36a8f28f26568fa/76956949509.pdfIn PDF document text
    • https://powermailer.in/userfiles/file/9517954390.pdfIn PDF document text
    • http://trinkhorn.org/userfiles/pimovozuvugerunafu.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/160abb39f01c99---13930014396.pdfIn PDF document text
    • http://fitviewer.biz/files/file/nikegexuzowufaveboz.pdfIn PDF document text
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160830482a34f2---64370506908.pdfIn PDF document text
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a165edd4b05---63513331467.pdfIn PDF document text
    • http://studiotecnicoprato.eu/userfiles/files/kuxoba.pdfIn PDF document text
    • https://tsegypt.com/file/78307000324.pdfIn PDF document text
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a30828efef1---57157670071.pdfIn PDF document text
    • http://mattstergamer.com/wp-content/plugins/super-forms/uploads/php/files/eg67sciqc5k60p67m36ha5pf47/kijumaguleluvujuzuve.pdfIn PDF document text
    • http://bhttourist.com/upload/fckimagesfile/12145690265.pdfIn PDF document text
    • https://skvacations.com/userfiles/file/lasosivejasogukix.pdfIn PDF document text
    • http://aweibel.com/Photo/file/23155781646.pdfIn PDF document text
    • https://rpitrade.com/ckfinder/userfiles/files/82988043190.pdfIn PDF document text
    • https://photographerin.agency/wp-content/plugins/super-forms/uploads/php/files/k3eha2td1jp5hfqmfd9so3ku45/darasepigadukuzofawafa.pdfIn PDF document text
    • https://ifacemount.com/wp-content/plugins/super-forms/uploads/php/files/r4kkn97mdoaruoi5ahiqnnbvlg/45960283040.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_off0000eba8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBA8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000103ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103BA 19516 bytes
SHA-256: 35c0f08e3f33e4463d2cf224a7cd8721fd026ade654ae4bd44839a8209f31f81
font_02_sfnt_off00013673.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13673 11156 bytes
SHA-256: c7da3ce12ff79547c64e1ffc39917d846922243f631ac8854b038d51cc205cf5