Malicious PDF — malware analysis report

Static analysis result for SHA-256 f31c68953ed13cf8…

MALICIOUS

PDF

83.7 KB Created: 2021-09-16 16:42:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 15a22a3e9a572a09373aac60907ee45c SHA-1: 88b54817ed58a6d23965ac7aa5a614ba84fb919b SHA-256: f31c68953ed13cf8bf07f5a4e922721b5dc563e0b2e72984da16d042ac84865e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF document that contains numerous links, many of which point to compromised websites or disposable hosting. The heuristic firings indicate this is a link farm designed to redirect users to potentially malicious content, likely for phishing or malware distribution. The ClamAV detection and ML classifier further support its malicious nature, classifying it as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://philabc.ru/uplcv?utm_term=download+leno+tv+apk PDF link annotation
    • http://www.barbazan-debat.fr/ckfinder/userfiles/files/60671576832.pdfIn PDF document text
    • https://wittnebel.dk/file/6862431788.pdfIn PDF document text
    • http://agppi99.pretty-match.com/upload/files/95853666752.pdfIn PDF document text
    • https://torrentclub.vip/wp-content/plugins/super-forms/uploads/php/files/1nsd20d025kds604haafmugjib/vetojefem.pdfIn PDF document text
    • http://airconbank.com/upload/fckeditor/file/31711325480.pdfIn PDF document text
    • http://marklaliberte.com/fckupload/file/sosej.pdfIn PDF document text
    • http://likebarcode.com/image/files/20210904_134933.pdfIn PDF document text
    • https://ichapps.peaceofworld.com/ichapps/ckeditor-ckfinder-integration/uploads/files/72805846192.pdfIn PDF document text
    • http://realestatespoznan.com/uploads/14432957844.pdfIn PDF document text
    • https://concurs-euclid.ro/upload/fck/57139494887.pdfIn PDF document text
    • http://xn--80aer5aza.xn--c1acndkmcarx.xn--p1ai/ckfinder/userfiles/files/32226075533.pdfIn PDF document text
    • http://davidhammerstein.org/ckfinder/userfiles/files/90497709255.pdfIn PDF document text
    • http://eng.sut.ac.th/tce/2016/administrator/ckfinder/userfiles/files/juladulusexezekoduvuxo.pdfIn PDF document text
    • http://belovosushi.ru/files/54067600113.pdfIn PDF document text
    • http://studioindelicato.com/userfiles/files/vemezuluvebunaxatuw.pdfIn PDF document text
    • http://chothuexeninhbinh.net/data/dulieu/files/11101274942.pdfIn PDF document text
    • http://chemonova.com/FCKeditor/file/tekowov.pdfIn PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1613126c1970e2---95347050217.pdfIn PDF document text
    • https://ysh.my/userfiles/file/92913160507.pdfIn PDF document text
    • http://win-sonic.com/ck_imgs/files/wulupigivapomaketasumafun.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16133a5970eca7---sojurixekuzixuzawaz.pdfIn PDF document text
    • http://everintelconsulting.com/upload/file/202109060544259661.pdfIn PDF document text
    • https://harmony-lazienka.pl/Upload/file/banizejemixoga.pdfIn PDF document text
    • http://opsir.eu/files/file/80102546374.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_off0000e155.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE155 10272 bytes
SHA-256: 7e9d6b8bcbf79323131864258d7888e2ca9f30d4c725fdee947c43b0d240d7b8
font_01_sfnt_off0000f899.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF899 18520 bytes
SHA-256: 119eb1f22eda3363f49323fd4aa71f3e5485ddfa6e8628b5e5c3537b621ce5a6
font_02_sfnt_off000128db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128DB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1