Malicious PDF — malware analysis report

Static analysis result for SHA-256 9f8458b6a37c86af…

MALICIOUS

PDF

69.1 KB Created: 2021-09-18 07:26:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a2f9499b7d44fd24cf52ee1c310edb38 SHA-1: 939350b249ae199613bddba92a4dab41f73e4798 SHA-256: 9f8458b6a37c86affc137d25b0538d04e0ec3ccdb50f2e06c76fda85fc5133e8
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, with numerous embedded URLs pointing to various websites, including those hosted on compromised CMS platforms. The presence of multiple external URIs and link farm heuristics suggests an attempt to redirect users to malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

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 https://fobh.net/userfiles/files/76196191494.pdf
    • http://ffarchitettura.it/userfiles/files/zaravexofinenozakafiz.pdf
    • http://hillcrestneighborhoods.com/userimages/87045455839.pdf
    • https://marblobaths.com/app/webroot/img/files/87688975050.pdf
    • http://kprmk.pl/userfiles/file/taragoratavuxavove.pdf
    • http://www.donboscovizag.org/images/files/51219656527.pdf
    • http://www.multigacos.com/admin/uploaded/fck/file/11365667863.pdf
    • http://exima.kr/userData/board/file/65406417671.pdf
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16142b08ef0ac5---32318538890.pdf
    • https://maffart-guy.com/userfiles/file/45299451392.pdf
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f3b8e77305---zegularus.pdf
    • https://mygrind.ie/userfiles/file/9343145266.pdf
    • http://grupomarsamo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f41196ab2e---jipapebome.pdf
    • http://brette-animation.com/userfiles/file/85775411479.pdf
    • http://enovosti.info/ckfinder/userfiles/files/sutazofizejefevu.pdf
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/43e901ec77ff646cfc4d04c98cca31f8/50948181497.pdf
    • https://used-machinetools.ro/app/webroot/files/userfiles/files/39780335292.pdf
    • https://dhesient.com/media/nuwanegegir.pdf
    • https://wsbe17hongkong.hk/_bin/ckfinder/userfiles/files/98705331694.pdf
    • http://jhdjt.com/images/upload/File/dipalesu.pdf
    • http://teaterskolen-efteruddannelsen.dk/ckfinder/userfiles/files/ligusotufisa.pdf
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613fb0cec4d24---nokexokezomoletujexiji.pdf
    • https://ruedi-leuthold.com/userfiles/files/polavipog.pdf
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/de01adai106t37fvvoh895je5n/libezodawatokowozera.pdf
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613182acaab9e---77287621273.pdf
    • https://altsovmun.ru/userfiles/file/74285565502.pdf
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/43e3c05b8f6f811a7a44f11d24d50c29/8642395396.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=torch+android+download
    • 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_off0000b45a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB45A 16792 bytes
font_01_sfnt_off0000cc71.bin
c6e73b04cf587f573111a147ce7b18692dfcaab65482c5034c0084132a98e163
pdf-font-stream PDF embedded font (sfnt) at offset 0xCC71 10116 bytes
font_02_sfnt_off0000e2e5.bin
1af4a84138f06770d42b1a0dd62137ea1a730c4cb5925cfb6e36164686ede9d2
pdf-font-stream PDF embedded font (sfnt) at offset 0xE2E5 14336 bytes