Malicious PDF — malware analysis report

Static analysis result for SHA-256 d1e87d883cd808c3…

MALICIOUS

PDF

81.8 KB Created: 2021-09-02 14:07:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: a564e18636752f51c73d4490db739c7b SHA-1: 75a87a1274c9da4d7499f42a2e5450f5de6c58ee SHA-256: d1e87d883cd808c3d160b97694dea29602b979532e1c6793df4700d3796fc479
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. It functions as a link farm, containing numerous URLs pointing to various domains, some of which are hosted on compromised CMS uploads or disposable hosting. These links likely serve as lures for phishing attacks or to distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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=regrouping+math+worksheets+for+2nd+grade PDF link annotation
    • http://praxis-greve-polley.de/web/editor/files/7644607716.pdfIn PDF document text
    • http://pincodehub.in/userfiles/file/3375983043.pdfIn PDF document text
    • http://kqcme.yiaiwang.com.cn/upload/files/33754492806.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cf51d2ddd3---88006109131.pdfIn PDF document text
    • http://bubblesoflove.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b50a607dbdb---tadopininerenaselozugurug.pdfIn PDF document text
    • http://gramercy-grand.ru/files/file/rizazufigemafirolawexus.pdfIn PDF document text
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a1ec1fd92ab---6192953148.pdfIn PDF document text
    • https://aeternoplanning.com/ckfinder/userfiles/files/98909662637.pdfIn PDF document text
    • https://netlandschool.cl/files/20044273922.pdfIn PDF document text
    • http://norilskgu.ru/userfiles/file/70442531606.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608002e78a18b---12236174105.pdfIn PDF document text
    • https://mps-india.com/userfiles/files/85819126338.pdfIn PDF document text
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16116b5de85168---dalapeguz.pdfIn PDF document text
    • http://bienbao.org/uploads/files/mawepudenopaguwak.pdfIn PDF document text
    • http://foire-fromages-et-vins.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1e984bcca9---35777476821.pdfIn PDF document text
    • http://kamnitikamini.si/upload/files/vezimezotipuxegerulowe.pdfIn PDF document text
    • https://chmelo.hu/sites/default/files/file/56270170261.pdfIn PDF document text
    • http://locke-3c.tw/uploads/files/202108242045129815.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/la71vtv3k1vg3j5oiups9sc5jv/ledajegaxolosilidenefogok.pdfIn PDF document text
    • http://angelescare.com/userfiles/file/ledowat.pdfIn PDF document text
    • https://thehideawayresortpattaya.com/userfiles/files/peroxogijukir.pdfIn PDF document text
    • https://xo-sound.ru/userfiles/file/62318743449.pdfIn PDF document text
    • http://lifemartrealestateconnect.com/wp-content/plugins/super-forms/uploads/php/files/vfkv89heu086v478ugdp5vbsl4/43120871302.pdfIn PDF document text
    • http://ristoranteibucanieri.it/userfiles/files/risanovi.pdfIn PDF document text
    • http://xn----dtbfdwc0aaaev8k.xn--p1ai/ckfinder/userfiles/files/xufipugikanesiwose.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_off0000d91e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD91E 17536 bytes
SHA-256: c31e7d1e7a35506252caa8a972b92136e0680ac9070a22aa4f304c9d26187e61
font_01_sfnt_off00010684.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10684 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011e9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E9B 11340 bytes
SHA-256: 48a0c5f5668164c7b5e74d461a821e89d2df7fd53699adcfbeffd26f04ca4991