Malicious PDF — malware analysis report

Static analysis result for SHA-256 b156e811a6bef891…

MALICIOUS

PDF

85.6 KB Created: 2021-09-13 00:00:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 62616cf505518de7ad85f9e9543aec55 SHA-1: 6035868a48dbf51e5a56d6308ba874ba71f1c1fe SHA-256: b156e811a6bef8917f41669d33ef138ce87b2a48e65206e3583eeee15c93da3f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised websites or disposable domains, indicating a link farm designed to redirect users to potentially malicious content. The ClamAV detection and ML classifier strongly suggest a phishing or trojan distribution intent. Although no scripts were explicitly extracted, the nature of the URLs and the heuristic firings point towards a malicious document, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

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://infrive.ru/uplcv?utm_term=fear+and+loathing+in+las+vegas+read+online
    • http://yangs-ns.com/ckfinder/userfiles/files/20210910201653.pdf
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/161365460bf519---45185687343.pdf
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/bb1d388afde226d99a2f4afbb6cd276d/90494230969.pdf
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161384efb8bfb9---ruxiginipigo.pdf
    • https://whiteplacard.com/UserFiles/file/potevuzaraponitoxiga.pdf
    • https://cakkue.com/contents/files/biboxafagamud.pdf
    • https://efsanepin.com/calisma2/files/uploads/57100760866.pdf
    • http://www.kzhep.in.ua/wp-content/plugins/super-forms/uploads/php/files/v46vpeaemvplr95rn87nsqr470/7712645601.pdf
    • https://weldingportal.it/userfiles/file/fetif.pdf
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/1612fc05c10e5d---32152528315.pdf
    • https://stakeoutllc.com/wp-content/plugins/super-forms/uploads/php/files/7a7b2bad15e9e9a5140710e18575c7a1/27121985617.pdf
    • https://angelsstaff.com/uploads/file/wademiwopenujoxi.pdf
    • http://transporteslaplata.com/imagenes_web/file/wetizewatazikew.pdf
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/1f911a2b286372fa4dce1d3d38ab1da5/fejiw.pdf
    • https://eastoncn.housemember.com/uploads/files/rakotomuwuloxadutiruru.pdf
    • http://epoxidice.ro/mm/file/sologesosemizisu.pdf
    • http://wonderpanel.com/app/webroot/img/file/lodatobagesomeduje.pdf
    • http://okeefesreef.com/ckfinder/userfiles/files/75735880552.pdf
    • https://standsimulator.com/ckfinder/userfiles/files/49277403508.pdf
    • http://thailaundry.com/imgUpload/files/kewiwizafuduxa.pdf
    • http://hakasasi.id/userfiles/file/kolevurisuzilid.pdf
    • http://asqcert.net/files/files/sisuxo.pdf
    • http://igigeothermal.jp/userfiles/file/puwosiladez.pdf
    • http://bielle-srl.com/userfiles/files/41180875041.pdf
    • http://associatedreclaimed.reclaimedoils.com/userfiles/files/mekelumuregifez.pdf
    • http://archgeo-leszno.pl/uploads/userfiles/files/35403548135.pdf
    • http://hissekurban.com/resimler/files/lugogijanosukudomilitulas.pdf
    • 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_off0000e4ab.bin
15276dfe07d1b278721c1731207164b2a206e144b6a498eb512f6f1384aafb2a
pdf-font-stream PDF embedded font (sfnt) at offset 0xE4AB 10572 bytes
font_01_sfnt_off0000fc7a.bin
18303aff87b9ad03482c79aa2fb8f987943a34bf0d0ea76f14e479a0e5c687c4
pdf-font-stream PDF embedded font (sfnt) at offset 0xFC7A 19568 bytes
font_02_sfnt_off00013018.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13018 16792 bytes