Malicious PDF — malware analysis report

Static analysis result for SHA-256 f03c98644f0847b1…

MALICIOUS

PDF

71.1 KB Created: 2021-09-24 18:22:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 2badcb21d362b516fcb5e2dd5bfd8dd6 SHA-1: 48774092266acd879f2a2088ef852a3a16a13d76 SHA-256: f03c98644f0847b1f8256e8ab19c8892a71a4cdddebcaf16bf8985f225a30e0e
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Numerous heuristics identified the PDF as a link farm, with many URLs pointing to compromised websites or disposable hosting. The presence of 'utm_term' parameters suggests an attempt to track user engagement with these lures, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://krisoc.ru/uplcv?utm_term=hanuman+chalisa+mantra+in+malayalam+pdf PDF link annotation
    • https://faresaldabbous.com/uploads/files/vixorotomukumosalavin.pdfIn PDF document text
    • http://bigyikesmedia.com/home/xtremweb/public_html/consultinstitute/web/upload/files/danexu.pdfIn PDF document text
    • http://windowsplusllc.com/ckfinder/userfiles/files/mokeluneguf.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/16142176e63a60---gotevudonotudabob.pdfIn PDF document text
    • https://vayamcs.com/content_files/files/46461530699.pdfIn PDF document text
    • http://studiotecnicobonoli.com/userfiles/files/dowejolidisurozaretaki.pdfIn PDF document text
    • http://candemdientu.com/Images_upload/files/tojawopuvepuwakasivunewu.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614ba453eb967---85571238433.pdfIn PDF document text
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/1614dbe3e75bbc---68789389736.pdfIn PDF document text
    • https://matfreklam.com/calisma2/files/uploads/72039694881.pdfIn PDF document text
    • http://classtool.info/upload/files/zorodomivelusi.pdfIn PDF document text
    • http://www.mezmat.ru/ckfinder/userfiles/files/regeguto.pdfIn PDF document text
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1614b27ae38b06---81259273227.pdfIn PDF document text
    • http://fullx.net/files/mukajusufakurifonupog.pdfIn PDF document text
    • https://natyabio.com/uploadfiles/54631061941.pdfIn PDF document text
    • https://alakharia.com/public_html/userfiles/file/28101372281.pdfIn PDF document text
    • http://rkmaster.ru/uploads/files/17379436536.pdfIn PDF document text
    • http://kirsanov-maslo.ru/uploads/xeladuji.pdfIn PDF document text
    • https://gullyracing.it/admin/ckfinder/userfiles/files/54011254639.pdfIn PDF document text
    • http://nincity.de/inline/file/28580576946.pdfIn PDF document text
    • http://altelaw.com/uploads/image/file/37843130698.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/xokabelamexorolosibutul.pdfIn PDF document text
    • https://durimawar.com/contents/files/18673202160.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_off0000b2c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2C4 10840 bytes
SHA-256: b2d3bc8c0f5f01f0d70e9eae1f0bdc1b8ae645e36642e66d72533a4cf79e98fa
font_01_sfnt_off0000cb7f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB7F 16836 bytes
SHA-256: 15d7e50caa721ae470e53e1604c392ada474f3f12e3a2380f7510dc4a5ff5e1b
font_02_sfnt_off0000f658.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF658 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1